So far , about season 220 I have not run into any issues. I gimped the map size down to medium on the 1.19e realese and had good results as far as the slow down.

Did the same with this realese and it seems to help. Only problems I have had so far is an issue with the harbor. I built a harbor, and trained a transport but could not get my boat in the water. I figured my placement was off, not far enough in the water to be able to move my boat so I demolished the harbor. I went to disband the transport and it would not allow me to do so.

I am going to try to build out my city so I can place a harbor futher down the beach and see if that helps!!

Also I saw a post  that the mid game slow down was fixed for large maps, is this really the case? I really like having time to build up before I run into the other factions but the mid game slow down was unbearable.