For me it is okay, everything depends on how much time you want to spend on simple cave.
Stone in the middle with wide path around is good idea,
I guess it is rotworms cave for beginers so paladin have plenty of space,
You can make boring cave with just 3-4 chaming "places" and everything will look quite okay:
-You did it already with bones and skull, can place there some rotten meat, bloodspot or broken sword
-You can do it with some mud and water + shrooms but remember it is underground and there shouldn't be many flowers
-You can do it with some wooden furniture and troll living there with small candle and hay to sleep
-You can do it with some slime and ferns, muddy footprints, and some ghastly eye watching
-You can do it with troll digging tunnel with pick (also quest for pick or just laying on floor)
-You can add just a 3-4 mixed stone and earth borders
I think shape is okay, always imagine that when player gets to dead end will be disappointed but you can cheer him up ith reward or just by creating loop so he can go back but with different path