It'd be kind of cool to be part of one connective universe like Marvel, but its not all done by one studio the way marvel does it, meaning there's different bosses. And they'd constantly be compared to marvel in terms of MCU, and they probably are afraid they can't do it as well, which is probably true.
Additionally, you lock yourself into and out of specific storylines when its all one big universe, ESPECIALLY when you have (at least) 5 ongoing episodic 22 episodes per season stories going on at once. Keeping continuity with movies would be a nightmare. Marvel has 1.5 network tv shows (both on ABC which is a sister company), and Agent Carter takes place in a fairly distant past, with the Netflix shows being shorter and more tightly controlled and limited in scope, without having to burn a new villain/hero every single week. This is a LOT easier to manage.
DC wants to rule comics TV, and for now it does, even though they bricked on Constantine.
To me, there's much more potential downside than upside for a DC connected movie and tv universe.
Those are some really good points and I hope DC is putting that much thought into it
I wonder what Marvel will do with their continuity when some actor's contracts expire. Will there be a reboot, or will they follow the comics and put someone new in the suit?