1. the current tactical combat could be made deeper and more satisfying by adding elements from the jagged alliance and x-com series. what i'm thinking of in particular is randomly generated battlefields with different forms of cover that can be used to protect ones own troops or to created ambushes by hiding. in Jagged Alliance there is also an emphasis on line of sight and range. This means that it's very important to get into a position that gives a good view of the battlefield in order to see enemy forces and hopefully a better one than than the enemy in order to shoot  them before they can shoot you.  Having all battles play out in this fashion would be tedious for a civ like game but it could work well if they functioned this way in more important battles like when enemy cities are about to be taken over or when quests are being solved.

Having a system like this would also open up a vast range of possibilities for new tactical spells, abilities and creatures that would be useful to solve different problems that might arise. a reveal spell for seeing if enemy troops are hiding behind a cover, a spell for destroying walls, flying creatures that can give advantages to line of site, spells that creates holes in the ground for protecion, troops that can build different forms of protection and siege weapons etc.