Good/evil toons can group togther, there is no issues there.

Evil/neutral toons are- SK,Bruiser,Zerker, Guard, Assassin, Brig, Troub, Dirge, Coercer, Necro, Wizard, Warlock, Inquis, Defiler, Fury.

If you do decide to go with a fury I would pair him with the defiler over the inquis. Can group ward then use the druids heals to catch up. You would be pairing the best single target healer in the game with one of the better group healers in the game. But you have a similar setup now so maybe you wanted to try another path.

I melee with my tank and dirge, any more then that for me would be too much and would lower the effectiveness of my other toons. That is the main reason I go with a caster heavy group, I seldom melee at all on my troub.

Your SK will get an end line ability in his EoF AA tree called Reaver or Reaving, it adds a lifetap effect to all your spells. Add that and the group and single target taps the SKs already get and they can heal themselves some to help lessen the load on your healer. SK also get a ton of "save" spells that will make you imune or far less able to be damaged for 10-15 seconds. Most of these are AA abilities, I know there are 3 that I can think of without looking it up. At 80 they also get bloodletter which is very useful and brings the number of saves up to 4.

TSO missions are not bad at all, you should try running them with your current setup. You cant get the shard missions until lvl 75 but you can run the zones anytime past lvl 50 for XP, AA and loot. I would start with the everfrost zones and see how you do. The real key to doing TSO zones is to have your tank geared as good as possible.

You are correct with everything you said about the way each healer does his heals. At 80 templars get a ward in addition to their two reactives, im not sure if an inquis does or not.