1. Complete control over my own body, Including the ability do control my own density, hardness, weight, muscle mass, allergic reactions, growth in general, regeneration to a reasonable extent, perception of pain, total recall of memories, death if I want to. Finally total control over the ability granted through my second wish; It being part of my body an all.
2. Selective complete reincarnation. That when I die, my soul including my personality and all of my skills, abilities, beliefs, and knowledge get stuck in a developing baby. But this knowledge is only revealed to me as I need it. For example, the first time I take a math class that life, I "remember how to do math that kind of math as soon as I see it, as long as I know how to do in in a previous life. I remember what a word means and how to pronounce it when I first see it or hear it. I wouldn't know how to talk at birth, I would need to wait until my vocal chords developed enough to say the words, I still follow normal physical development. Also my knowledge of my other power works the same way. As soon as I have the need to harden my skin I can, for example the first time I get cut or otherwise get hurt my memory of regeneration and hardening my body comes back.
3. That every time I turn 18 I remember everything form all my previous lives. Until I decide to forget(wish #1). That or something that fundamentally changes how the world/the universe/humanity in general functions.
Not really sure how all this would pan out, but I would be interesting. and If didn't like it I could just change the terms of my next reincarnation. If seems like every-time I start thinking about one of these three wishes threads, I dome up with a different more advanced set of wishes.