That being said, I currently feel like Heist is such a big addition that if you focus on it as much as on mapping you don't progress mapping much at all, so for now I'll solely progress the atlas and stash the contracts. That's not because I don't enjoy it, but because I don't necessarily want to do it now and I'm sure it will feel better next week.
I'm also playing a pretty damn tanky char so I'm not having many issues with the escaping, but I can see those mobs camping at the locked doors and shooting all at the same time being a large issue for many people.
Performance has been stellar so far for me, zero lags and crashes. Best league start ever in that regard for me.