EQ2's macro / priority system is from top to bottom, with the exception that the very last spell/ability in the macro will be queued up second - but even sometimes I'm not sure..

Typically how I do this then is put my most powerful spell first, then second most powerful second, etc. But I also put the first spell at the bottom as well. Easy problem solved :P

I don't use HO's at all, I should probably try to add it in, just for the fun of it but I don't think the benefits it gives these days are worth it.

Quest turn in's are a chore, which is why I enjoy dungeon grinding.
Basically do all the talking on main, accept quest. Share quest, broadcast to accept. Turning in is a bit of a pain but typically quest turn in's are at max 2 chat bubble clicks. The rest is a follow up to accept the next quest which you don't have to do since the main will share that one.