I like the putting up alot of bugs, have been thinking about some of these too.
"Severe hang time on tactical battles if you choose to defend"
seems be to mostly heroes on my part, and more often if its caster heroes using a shield + defend. (haven't seen it on pass yet).
"When viewing cities to build, if you exit the build menu from a city that you did not original click it will not reset the camera view."
"If you end turn while in Build mode the camera does not return to the previous setting."
- both these seems to incline that you have set on the "enable city build zoom mode" in the options, I tried it, but it would usually stop my camera in weird angles so I figured it badly flawed and stopped using it.
"Loading a saved game caused terrain features, buildings, etc not to appear on the map. Forced restart."
Also usually causes explored terrain out of line of sight to become "non explored" (you can see the mountains and forests, but not notable locations and monster lairs)
"Mounted enemy unit does not show the correct amount of moves it has."
This seems to be a particular problem with the wildling rider, but have seen in once or twice with mounted heroes, else it works perfectly for me, have you checked for the "charge" ability?
Want to add something I just found.
If you double click a unit in tactical battle, right after finishing the last monster (was done with a spider), it opens the stat screen, you win the battle, and the game gets confused and crashes.
When you have a stack of 5-6 heroes, and enter a battle with an air elemental (or anything with titan's breath, that knocks all you're heroes prone), you have to wait Excruciatingly long for each hero to play an animation to stand up, one at a time... paaaaiiiin.
Hope you don't mind the extra input 
Sincerely
~ Kongdej
