Abandonment: is it possible to remove or significantly reduce the penalty(to -1 or -2) for abandoning a settlement as as you can get ridiculous penalties if you want to do a scorched earth strategy. e.g abandoning Britannia as WRE gets you -50 across all provinces.
Movement: due to the AI's focus on raiding in Attila it means you need to chase down incursions in your territory, but they seem to have the same movement points in your territory as you do so you spend a lot of time and manpower chasing hordes as they sack their way across your territories. A solution to this would be to increase army movement in friendly territory, this gives the benefits of: Chasing down raiding forces quicker, moving armies across your ever growing empire faster to respond to threats, and also it seems more realistic for armies to move faster in their own territory due to lack of resistance to invaders and better knowledge of routes in the area ( Huns won't know Italy as well as Romans){perhaps tying the movement bonuses and penalties with the happiness of the province e.g inspired=20% bonus and penalty, outraged 5% bonus and 5% penalty .
Also i find that fleets are not very useful in Attila giving them more movement would allow them to control (and raid) more coast and sea with greater efficiently.