The big problem I've always had with shields is that they don't regenerate in combat and they take absolutely forever to recharge back to max. I remember something like 20 seconds out of combat to recharge the 1200 or so shields on my Frost...so them tanking more damage is cool and all, but it won't make them much more useful if they don't come back significantly faster. I honestly think they should come back all at once instead of the slow recharge over time, just refresh the full shields after 3 or 4 seconds of not getting hit.
Edit: Checked the wiki for math: At 1295 shields, it takes me 1295/(15+(0.05*1295)) = ~16.25 seconds for a full recharge. You said in the Hydroid rework you removed Undertow because it was basically sitting still in a looter shooter, yet me having to wait 16 (+ 4 seconds if my shields were entirely broken) seconds for my shields to come back out of combat isn't a problem?