Tier 1 Anti Air

My only problem with that is when the opponent doesn't have detection with them it ends up not working well as a "tank", because it only does that effectively when it has the bonus regeneration.

So I can get a lot of use out of my roaches by recycling them to the back and having them burrow-heal, but those roaches really aren't tanking or shielding anything. Instead they just become a highly recyclable unit, not a damage sponge.

I'd almost rather have them be able to go into a non-combat mode where they are still visible but regenerate health faster. That would allow them to work as a front line damage sponge unless the opponent micro'd their units not to target them. This wouldn't take away their ability to move while burrowed, but would shift the condition of their regeneration from being burrowed to being put into a non-combat (let's call it "shelled") state. Sort of like Gargoyles in WCIII actually, not that WCIII was the inspiration for this idea.