Mostly in RPG Maker count of events impacts on game performance because RPG Maker always updates information about events. I checked that when I ported my VXA project to MV. In VXA 200 events on map don’t influence on performance. MV project starts lags. And I think better to use one parallel event than 50 events.
With “function can be made in one event but not graphics” I mean you can use event’s script in one event instead of 2 (or more) but there will be a problem with graphics. I just used to do regions and conditions (if you checked my translation which I sent in DMs in gamejolt). For different objects you can use conditions about region and coordinates. And I think update in one event will be more comfortable than in 10+
Maybe I’ll start to optimize this game again.