Simple to learn:
It takes time to learn any package and become reasonably proficient, I have been using my software for over 6 years and still learn new ways with every book or tutorial I see.
Not to complex:
To be honest as long as you can create a primitive, extrude it, chamfer edges, weld vertices,scale, wrap an image to a polygon thats all you really need, I dont use much more than that under normal circumstances.
Fairly powerfull:
See above
Good for weapons, characters and objects:
They can all do this, It depends how much time you are willing to spend practicing. The more you put in the better you will get. No modelling software has a button to make a mesh awesome.
I give ip with thos baner fing as it never seems to work for me. I woll now stop wasting mu time.