Pretty good so far.
Meh, somewhere in there... probably. It's not that critical. At some point they're a little more effective, and then later a lot more. You're not gimped if it takes you a few levels.
It can be, but it can also get pretty deep. There's set bonuses, damage procs, Hami-Os...
You can spend a lot of influence buying rares and winters and still end up only making a character marginally better. With careful planning and specific goals, you can make something extremely powerful.
If you have enough damage and accuracy, you're not running out of endurance... your character is fine. The forums make it seem like everyone is min/maxed to the gills, but that's not the in game experience.