Many buildings dont need changes. Others only would need bigger doors. A few only need to be a little taller (little). And for the last the production buildings (stables, barracks, archeries, etc…) that need a redesing because they were reduced by more than half and this couldnt be fixed. But wouldnt be neccesary a complete redesign.
For example see the stable:
Visual enhancement of buildings without compromising playability - Age of Empires IV / IV - Discussion - Age of Empires Forum
The thing is that these changes only would have the game more beautiful and dont affect the gameplay.
And if you want I can share surveys where it is seen that most people would prefer better proportions