If you want to show your love for Mew, then by all means go for it. I don't think you should be asking the masses here because at the end of the day it's a permanent mark on your skin. You need to be 100% behind it and not influenced by anybody else.
As for me personally? I have considered getting a tattoo for a while and yes, I'm really into Pokemon, have been for a lot of years and everyone and their cats know who my favourite Pokemon is. Yet there's always this pessimistic thought at the back of my mind asking myself whether I'll be a Poketard and a fan of Sneasel in forty years time. I would like to be, yet I doubt that quite a bit.
Yet I want something Sneasel-esque. /lawl WTF is that word
So I'm gonna get a small tattoo of Sneasel's National Dex number, 215, done in the Georgia font and placed somewhere where I can cover it up, like the top of my arm or down by my ankle.
/TL;DR