The picture is clear, but as I said it is really up to what kind of motion your character will make wether it needs more ik or not. Personally I would not include ik's in the arms, maybe a spline ik for the spine. For sqishing and stretching the body when moving your legs. You might want to use the paint weight tool which is in the animation tab. It is too complicated to explain here. So i'd suggest you look in the maya help, or do a google search on "maya rigging" or similar.
If you want a good introduction into rigging do the low poly rigging tut. I've done it it surely helps, explains everyting from making the skeleton over ik's spline ik's driven key's, skinning, paint weights and includes a walkcycle. otherwise google is the way