Only really fun way to play D3 is together with a friend/friends, IMO. It's somewhat entertaining to solo beyond normal IF you buy a bunch of stuff from the auction house every other act or so, but failing that the game becomes hard and frustrating and a slow, slow grind since almost all the gear that drops is so incredibly, painfully shitty.
Eventually you end up ten levels higher than most of your gear, and killing enemies start taking forever - especially random named mob packs. These are often much more lethal than actual bosses, which is fucked up to say the least.
Right now I'm soloing my demon hunter in act 3 nightmare where I have hit level 47, roughly halfway through, and my mate and I play wizard (myself) and barb (him). Coop is like...20 times more fun even though we're only like level 35ish or so, and still only just past skeleton king in nightmare.
I've now picked energy beam with split rune, electric sparks with explosions on death, familiar with extra damage, lightning hydra, meteor with lower cost and lightning with chaining rune. Also, glass cannon passive, the one that regens arcane power when you shoot signature spells and some third one which I can't remember now...
This setup's quite fun, I haven't tested it together with him yet; I had shock pulse and frost nova instead of meteor and familiar, which is a much safer setup. Running around with all offensive skills is exceedingly dangerous solo, I almost got killed several times against random elite packs since I had no defense... Lol. Not good maybe, but it's easier when my mate tanks for me. If I start doing poorly I'll just replace familiar with frost nova again, but the idea here is that most mobs shouldn't reach me, they should die to our overwhelming damage...
We'll see how that works. With the cheaper meteors I can toss down four of them before I'm out of arcane power and I've got an OK staff I dredged up with my demon hunter from a later act.
The game's reliance on weapon damage makes wands+offhand quite ineffective for wizards, plus it's much harder to find two good items to put in each of my hands than it is to find just one decent staff. That's a real problem, IMO. Staves are easier to manage, and they hit WAY harder. Same thing with barb, my mate says. Twohander just kills much faster than two onehanders. Bad game design on top of bad game design equals BAD. But it's not a catastrophe, and we're having fun together.
