I second this sooooo very much. I think it would be really neat to implement maybe a choice, whether by choosing a particular class quest line or through a skill path, where we could have those connected to nature, elemental and those connected to the spirits/undead. I myself rarely play magic based characters in any game (more of a melee player), but Necromancers have always had a place in my heart (I promise I am not morbid, haha) since Diablo 2 first came out, so if given a chance, I choose Necromancer as a main magical class. The only downside of that is hardly any games since Diablo 2 (apart from Diablo 3) have given us a TRUE necro. I am not talking about warlocks or even Death Knights, but a true Necromancer. Skeletal warriors and magi minions, golems, blood magic, spirit and bone magic, etc. Minions that will reside by your side and not just stick around for a minute or two, at the very least a golem, ghoul, etc. that could be a permanent summon and have the skeletons and such be quick summons that are on a timer or skill duration.
So if at all possible, if this could be a part of the summoner class or even a class on it's own, I would be beyond happy, haha.