This is tough, for every choice I would like I can see the down side. A lot of the downsides would not be good. Like walking through walls, you just never know what is on the other side, and if you do not look first you could fall a long ways down,I have seen a lot of homes/castle with one wall right on or next to a cliff. walking through walls does not mean you can not fall or be stabbed or shot.
Mind reading always a dream, but I can see the nightmare of it, hearing another person's thoughts, people are mean enough on the outside, I would really hate to accidentally read a very hateful mind.
X-ray vision, that could be fun, but kind of a useless power. I can not see to many problems with it, but also I can not see to many benefits.
So immortality, or very very long life. I think that is the one I would like to have. I can see it being boring, and I can see the pain of loss, of losing all those you at one time or another loved, I can see it turning a person jaded, but I can see all the positives of it too. So yes, I think I would make a good immortal.
Yes, I think the idea of a superpower being a mixed "gift". Initally, we focus on the benefits and only see that, but to every situation, there is advantage and disadvantage, and only by a bit more careful thought can we see that the initial rush of power is dulled by unexpected consequences!
I hadn't thought of being immortal! Imagine being there for all the important events of human history (past and future) and of all the time that you would have to learn all the mysteries of the universe! At the small cost of losing your loved ones over time...
The winners and the new question (I've told you how to do this before...) is here:
https://steemit.com/newbiegames/@bengy/steemitbasicincomegiveawayivetoldyouhowtodothisbefore-pb6n4om11j