These are two topics.
Lets say we meet 20sec after my spawn, I kill you with 15HP left and my next spawn is in 4 seconds. It would be useless to wait another 5 seconds until someone else kills me, so the only choice is to kill myself to support my team again with full HP. I do the same if I'm out of ammo. (Guess all of these ETL players would agree on this ^^)
Edit:/ If I'm infight with you and another one your strategy works, because your mate will have 3 med packs and keeps shooting me. In that case I can't kill myself right now. But even if I could, you mate can move on.
If someone is hitting me hard right after spawn (e.g. venice 2nd spawn as Allies), I go back and start the round again. I cant push any mate to plant or drive the tank in that case, so I need full HP.
Regarding the self heal. Please consider to "self heal" the moment a medic heals a team mate. I've seen it on different servers and with this you have to support your mates but also will benefit from it. And in the end - again - please don't increase HP of any class. If you want to adjust HP, reduce Medica maximum to 140 (instead of 154 right now)
Off-topic: @froggy You are safe from me the next days