Ease vs Ambition (the good, not-overtly-aggressive kind of ambition)

is it such a terrible thing to be far far happier doing something very straightforward and undemanding and unglamorous and a bit nondescript than you are when doing something a lot more specialist which supposedly encompasses all your interests and obsessions and will theoretically (although by no means definitely) lead to far greater things on a long-term basis?

Which is to say: am I allowed to prefer the idea of working quietly and consistently and unspectacularly to that of doing something challenging and self-improving and, like, rilly rilly a bit cut'n'thrust?