I think it's a good idea to get the form together before moving up. You're right on the cusp with those 3/4 pull-ups.
I don't know the answer on doing more pull-ups. Cheapo, who is an extraordinary role model, advocates just playing on the other days. In my own experience, I think I need the extra upper-body work, so I do some extra pull-ups on Mondays (D1) and extra push-ups throughout the week. Maddog has started adding the Convict Conditioning program, so we'll see how that goes.
The levels are really pretty big steps, so unless you are coming into it from a pretty solid foundation, you have to accept that you are going to be at each level for a while. (I'm now on 5 months at level 5, with level 6 still far over the horizon). The motivation has to come from seeing the incremental progress each week. A nice thing about simplefit is that since the routine is the same every week, and since everything is timed you can clearly see that progress on a month-to-month basis, even if some weeks are little up or down.
When your male ego complains, just look around and ask how many of the 37 year-olds you see can do even 1 pull-up.