It sure looks VERY nice, but is also too detailed and messy, for my taste. I agree with you, that caves are not that straight, but it's all the convention - the style/design you choose, should suit your needs, what you aim for. We all move in fantasy worlds here, right? I never wanted to recreate reality one to one. Also, that creation of mine is not exactly a cave, more of a underground passage, and just a part of it, as you can see.
That said - thanks for the input, I think I will improve my cave above (add some touches here and there).
Take care!