What's the best way to use the Healing skillset in conjunction with a system? In both bashing and PvP? I would love to use my Healing skills more, but is it even viable/useful in a non-PvP situation if you have a good system? Throw up some auras and don't worry about it?

Auras are situationally useful in bashing. You really have to have a system that works with Healing, though, or just turn it off and let the auras tick if it's low priority. I aura breaks for cave fishers, temperature for frost wyrms, and that's about it so far. The rest I just turn m&m's full healing mode on and the system just uses Healing instead of cures that actually cost money.

On m&m - fullhealing for bashing, partial for pvp.

(you can play with full for pvp as well, it can be pretty awesome but pretty dangerous in some situations too when you're kept unwillingly kept offbal)

Or against classes that suck away all your mana i.e. telekinetics, heavy bleeding.

Runes. Yes, I'm talking about you, Viynain.

I don't find that an issue, because setting allowed manause will have the system use normal things when your mana isn't high enough.

Auras are very useful for both combat and bashing, health auras can give you the edge you need to comfortably take something for bashing, plus sometimes your system wont have the lines for certain denizens so if you have the right aura up you don't have to worry. In combat auras are niiiiice so long as you bring the right ones to the game, I usually have health, mania, muscles, breaks and blood up but it varies.

That's true, but how do you deal with the massive bleeding? Well in my case I have <4000 hp...

Only option is to get away and sit and wait a long while while chervil, clot, and mana regain do their work. Typically 2k bleeding for me means it's time to go and spend a few good mins clotting it all away.