I can’t personally speak on the banking side. e/os has micro g implemented now, and on my device it passes the safety checks associated with it. To be fair though I can’t give a full endorsement for how well micro g works as a whole (I’m not logged in) In general I’ve shifted to FOSS apps so my sample size for google play services reliant apps is limited but the one’s I have used, open fine without annoying pop up errors.
Worth mentioning to those unfamiliar with e/os is it comes with a built in app store “app lounge” that also has access to play store apps so you don’t even need to go to the effort of installing aurora. One less thing you have to do