I know that PSGs are supposedly "new technology" but I think they should be worth more than 3 shots from the borg, so here's what I propose should be done about this.
1: Endgame (STF sets etc) PSGs should have their caps raised to 500-750, this will give them a few more hits before exposing your health bar to damage. (all others should have their caps increased accordingly)
2: Endgame PSG resistances should also be raised, they're silly now
3: Reroute power to shields should become the ground equivalent of Emergency power to shields (with respective level increases for example: RPtS 1 = EPtS 1, RPtS 2 = EPtS 2, RPtS 3 = EPtS 3)
4: The shield generators on engineering kits are laughable, I think they should get a slght boost to regen and to resistance
5: I think the medical generator should also get a buff (off topic I know) as they are just as laughable
I can't think of any more things to add to this list but all of these things would make PSGs a lot more useful and add to the Engineers ability to assist the team with bunker fabrication. We all know that Science can use the medic kit to health tank (which is in NO way a call for a nerf, it's a GOOD thing) but I think that Engineers should be the counterpart to this with the ability to shield tank.