Hunt wherever you are comfortable. Is higher better? Probably-but not if it leaves you feeling unsafe. Or not if you don't go out because you don't like to go high.
I shoot most of my deer from the ground now, including my last two archery deer- not because I'm afraid of heights but because I like hunting from my feet. But when I use my climber my rope is marked off at 18' and thats usually about the height I go to.
I also have a couple 12' ladder stands and one 18' ladder stand. Hang on stands I've used from only a few feet high to one that was probably 35 feet high one year. Wish I had a picture of that stand.
Is higher better? Probably. But not if it's taking away from the enjoyment for you.
-Jake