Stable level effects horse training speed. Unless you want to spe******e horse training to particular cities, build and upgrade your stables everywhere.

Build Inn to enable a feasting hall but possibly demo after hall is built. Keep a high level inn somewhere as heroes can be lost. You could rely on capturing but it'd be a hassle finding good ones.

You may as well not have any barracks in a town if you've only got 2. 2 is just an honour engine for other players.

High level beacon tower is essential. Without it you'll get no info on incoming army strength, the player attacking you nor the attacking town. All this info give you options.