I think you should wait until you fly your trainer a little; then you will have an idea of where you want/need to go.

I have seen people solo the first day out, and others need to break several trainers before they can fly and land consistantly; the majority of flyers are somewhere in between. Every one's aspiration for a second plane depends on their abilities and taste.

I don't mean to brag, but simply want to illustrate my point. I am one of the fortunate ones who soloed the first day: I learned to fly on a .20 size low wing plane called QB 20L made by Pilot (and I never crashed this plane). My second plane 5 months later was a Goldberg SKYLARK 56. My aspirations were always to fly aerobatics, and I never had a desire to fly warbirds, slow planes (like CUB), etc...
BTW the "quick learner" has a major draw back called over-confidence especially in your late teens, early 20's. I proceeded to crash many planes over the next few years by simply being cocky.

The bottom line is: try learning to fly the trainer, and look around to see where you want to go in the hobby; there are many areas of interest, and the guys training you may not steer you in the direction you want to go. Then you will have a good idea of what your second (and third...) plane should be.