Regarding the Attack vs Capture:
I think it would be best to add a couple of global game settings to control whether the default action is attack or capture.
Maybe separate the defaults for 3 (or more?) groups:
1) Civic Centers and other buildings that don't decay (don't need people garrisoned to keep it, when not in own territory)
2) Defense Towers and Temples (maybe also include buildings that train troops, like barracks)
3) Other buildings (production buildings, etc)
The defaults can all be set to Attack. So that will keep the current v27 behavior.
I would personally set the first group to Capture, and leave the others set to Attack.
