I only know hold 'em.
It would be wise to learn other variants, and I aim to one day.
1) I might find them more fun!
2) I might pick up another game easily, being somewhat of a natural when it comes to understanding the concepts. Won't know until trying!
3) Smaller player pool means that in theory it's easier to become one of the best. I'm not sure I'm aiming to become one of the best at anything but if I was!
This would be countered by the fact that there's fewer complete fish trying the game out and giving away their money. You would be that fish at first actually, playing against specialists in another game. Still, with a shallower playing pool there's less people to go through to become one of the best.
With fewer books, videos, and other learning resources out there for other games compared to hold 'em, they seem to be less understood. Perhaps someone with a much bigger brain than me could gain an advantage, coming up with new effective strategies.