Oh wow, that's a really hard question!
Growing up, there was a million people I wanted to be. When things are going crappy, I always think how better it would be if I were someone else.
There's always scenarios when we just want to be somewhere/somebody else. At least, that's common for me. Would we think that way if we weren't spoon fed what's 'acceptable'? If we didn't see what was considered beauty, would we want to be that person who's deemed so beautiful?
I think it's better to find out where that craving to be someone else is coming from, rather than to succumb to it. So many people feel the same way - it's best to look into something like that.
But back to your question, it would be easier to be anything that's acceptable and 'easy' in whatever society you live in. If it's wealth that would make things better where you are, then let's be a rich person. If it's a beautiful/fashionable person who has popularity, then be that person. Etc. etc. A lot of black people would be white if it meant an easier life and just being seen as beautiful, etc. (Wonder if that has anything to do with black programs such as BET, to encourage self-appreciation, hm.) And vise versa, believe it or not.
If I could be anyone else but me, I'd like to be the person that knew how to 'beat' typical human emotion.