There's one theme that hasn't been fully depicted yet but that seems to add up:
Sanity of high level ability users.

Why that theme?
Well we had the ability acceleration arc, that had people fry their minds/brains.
We had the accelerator, who was losing sanity and fried par of his brain.
We have now that level 4 teleport who was also losing sanity.

I guess that when the level rises, the burden on the brain and mind become difficult to cope with. After all, they use their brains at full capacity to bend reality. At some point, I guess it becomes difficult to keep track of what is real or not.

I found a little gift, by pure chance, I do not think we've had this here.
It's an ability+level generator based on your name (or any input):
http://kyubuns.info/ss/

You can try it with names/surnames. It changes with name position (when multiple input) accents etc... as it seems to be purely based on ASCII (or equivalent)

My best combination is my second name and first name with majuscules at the begining of each, giving me a level 5 that reads:
能力名： 原子使い ( メルトマスター )
Level 5
解説：「粒子」または「波形」の電子を、生み出し操る能力
Google translates:
Guest capacity: use atomic (Merutomasuta)
Level 5
Explanation: "particles" or "wave" of electrons, creating the ability to manipulate
I wonder if I'm a railgun too