I personally think that everyone is free to do whatever they want with their skin.
As for me, I don't have any tattoos and I have no definite plans of getting one either, although I'm not completely ruling out the possibility. As SikStyles said, it would be pretty cool to walk around with your own design on your skin. I'd probably want to create my tattoo pattern myself too.
Though, speaking of what's aesthetically pleasing, I think one should still have some sense of moderation with their tattoos. Most people get like one or two smaller tattoos somewhere, which doesn't look out of place. But some others get several huge ones, covering large parts of their body, and often, the tattoos also look significantly different from one another (and feature random and silly objects) - and imo that just doesn't look good.
This guy's tattoos look pretty awesome, though...