When it gets above 80 planets plus all the ships and starbases it can get tedious. Especially when you direct control all.
Yes it is fun for those that like multiple things to do. Even though it can be a bit much at times. On this train some would be turned off by doing all that micro.
The most time consuming is when someone gives you all their stuff and it take 40+ min to get it straight.
Like you said the large empire UI update will hopefully help.