In this post I will try to explain how to select heros, a way to build up hero stats quickly, and the types of heros you will need, and how to use them.

First, how to select heros.
The level number is irrelevent, don't select a hero just because it has a high level. Attribute number by itself is irrelevent, do not select a hero just because it has a high attribute number on one of the attributes. The most important stat is base number which I exmplain in the next paragraph.

Base Number. There is a base number for each hero that is given by subtracting the hero level from its highest attribute, this base number is important because it restricts how high your hero can go and how long it takes to get the hero upgraded. Do not even consider a hero with a base number below 60. Example 1. You see a hero in the Inn that has an attack of 69 and a level of 4, the base number = 69-4=65. This is a good hero. You see another hero in the Inn that has an attack of 80 and a level of 28, the base number is 80-28=52, this is a bad hero.

Base number is far more important than the actual number of the attribute you care about. Compare two heros. Hero Crackhead has politics of 70 and level of 1, base number = 69. Hero Slackjack has a politics of 89 and a level of 48, base number = 41. Crackhead is a much better hero even though Slackjack has a higher politics number.

Some general rules.
Inn. Do NOT upgrade your inn over level 1. If you have already upgraded it over level 1 tear it down and build a new one and stop at level 1. When you recruit a hero you want its level to be as low as possible and the attribute you care about for that hero to be as high as possible. For example, I recently found a hero with a politics of 70 and a level of 1. This is a GREAT hero.

Base Number. You want the base level to be greater than or equal to 60. Don't even consider a hero below 60.

Holy water and redistributing attributes. The time to use holy water is when you first recruit the hero. Usually you can get 1 to 3 attribute points to redistribute to the attribute you care about. For example, I recently found a level 1 hero with an attack attribute of 64. Using the holy water and redistribute, I picked up another 2 for the attack attribute, raising it to 66. Using holy water when the hero level is very low only costs you 1 holy water, if you wait the cost will be prohibitive.

Hero Hunting. You can do hero hunting without the hero hunting item. You can use gold instead. First, upgrade your feasting hall so that you have an empty space. Second, check the Inn for a hero. Recruit the hero. If you don't like the hero dismiss the hero. Keep doing this until you get a hero you want.

Second, how to build up a hero's stats quickly.
To increase the attribute of a hero you have to attack something. The more damage you cause on the defender the more experience you gain. Experience is how you increase the attributes. When you are brand new to the game you will have very few troops. To increase the hero attributes you will want to plunder NPC cities and valleys using the troops that will cause the most damage to the defender. There are many posts in the forum that explain this. Here is how I upgrade a new attack hero. Assume the level is low, say below 5, this hero will have something like 300 experience.
Only attack valleys that are close by, say within 8 miles, if you don't have valleys at any of these levels close by just skip that level.
Attack a level 1 valley with scouts.
Attack a level 2 valley with scouts.
Attack a level 3 valley with warriors.
Attacka level 4 valley with warriors.
Attack a level 5 valley that has no archers and no cavalry with archers.
Attack a level 6 valley that has no archers and no cavalry with archers.
Attack a level 7 valley that has no archers and no cavalry with archers.
Attack a level 8 valley that has no archers and no cavalry with archers.
Attack a level 9 valley that has no archers and no cavarly with archers.
Attack a level 10 valley that has no archers and no cavalry with archers.

I do it this way so that the hero's attack attribute is increasing as the defender I am attacking is becoming more powerful.

When attacking a valley that contains no archers or cavalry you send the same number of archers as the total number of troops in the valley plus 1 scout, 1 warrior, 1 sword, 1 pike, 1 cavalry, and 1 cataphract is you have the techs to build cataphract, don't worry about it if you can't build cataphract.

Alternatively, you can attack a valley containing only archers with cavalry and 1 archer.

Also use the hero to attack NPC cities. You can attack low level NPC cities with warriors. For all of these you can use a few other troops for a rainbow to minimize losses.
Attack a level 1 NPC city with warriors.
Attack a level 2 NPC city with warriors.
Attack a level 3 NPC city with warriors.
Attack a level 4 NPC city with warriors.

Now you need ballistas to attack level 5 NPC cities, you will need 500 ballistas and 500 transports, less if you have level 10 techs. I use 400 ballistas and 400 transports but all my techs are level 10. There are some good posts on the correct techs you need, always keep archery 1 level above horseback riding and keep compass one level below horseback riding.

Add 2,000 warriors to your ballistas and transports and you will get 140,000 experience.
So to attack a level 5 NPC use 500 ballistas, 500 transports and 2,000 warriors. (Or fewer ballistas/transports depending on tech level and hero level).

To attack NPC cities above level 5 you will need: 95,200 archers, 2994 warriors, 1800 transports, 1 scout, 1 worker, 1 sword, 1 pike, 1 cavalry, 1 cataphract. You will also need high attack attribute, start attacking level 6 or level 7 NPC with your 100 attack attribute hero, then when losses become acceptable move up to level 8 NPC, when losses become acceptable at level 8 move to level 9. Level 9 NPC gives 1 million experience. When attacking level 7 and above NPC always use the war horn or the ivory horn.

Politics and intelligence heros are trickier because they will have a low attack attribute. For these you will want to start out attacking valleys and low level NPC cities with warriors as above. The difference will be that you won't want to attack higher level NPC cities unless you have 95,200 archers. Then you can use the politics and intelligence heros against Level 7 through level 9 NPC cities. IF you have all military techs at level 10 and a war horn or ivory horn. Do NOT attack level 7 and above NPC cities with low attack heros if you dont' have level 10 military techs and war horn or ivory horn.

Third, heros you should have (and how to use them)
Note. Upgrade your feasting hall to level 9 as soon as possible. Keep the inn at level 1.

1. Construction hero - 1 of these total. This hero does ALL major construction. This is a hero with high politics attribute and when he is not building something he is plundering nonstop. The goal is to get this hero's politics attribute above 300 as fast as possible. The difference in the time it takes to build something with a hero with say 300 politics vs a hero with 60 politics can be quite staggering. You dont' have to leave this hero as mayor after you start the building, you can switch back to the city's real mayor.
2. Production heros - 2 heroes for each city. These heros serve as mayors. Each of these is a hero with high politics attribute. The reason that you need 2 of them is so that 1 of them can be plundering while the other 1 is serving as mayor and adding the production bonus. You keep swapping these 2 heros back and forth between being mayor and plundering. You use the one with the highest politics attribute as mayor and set the other one to plundering nonstop. You want these heros above 200 politics.
3. Research heros - 1 of these total. This hero does ALL research. This is a hero with a high intelligence attribute. When he isn't researching something he is plundering nonstop.
4. Scouting hero - 1 of these total (can be research hero). This hero does all scouting where the target is a higher level than your informatics and beacon tower. This is a hero with a high intelligence attribute AND a high attack attribute. This helps early on when trying to scout something that is a higher level than your informatics and beacon tower. Later on it helps when scouting against other players. Weigh the intelligence attribute over the attack attribute but don't neglect the attack attribute. Some people use the research hero for this role. I have one of each.
5. Troop recruiting hero / main attack hero - 1 of these total. This hero recruits/trains ALL troops. This is a hero with high attack attribute. When this hero is not recruiting/training something he is plundering. Use this hero for as many attacks against high level NPC cities as you can. Always favor using this hero first when attacking. You want this hero at attack 400. The difference in time it takes to recruit/train troops at 400 vs say 50 is mind boggling.
6. Attack heros - As many of these as you have slots in your feasting halls for after providing for the heros listed above. THe goal of these is to get their attack attribute over 150 ASAP. Why over 150? Because 150 is about the range that you can profitably farm NPC level 10 cities.

Here are the heros you should have:
Main city:
1 Construction
1 Troop recruiting / main attack
1 Research
1 Scouting
2 Production
4 Secondary attack (3 if your feasting hall is level 9)

All other cities
2 Production
7 Secondary attack (6 if feasting hall is level 9)

For the other cities you want to keep one slot open in the feasting hall so that you can move other heros in and out of the city to accomplish other tasks like research, construction, troop recruiting/training.