Hi John,
I'm certainly no expert, but if you're dead set (which I can understand) on the turntable, it seems to me that it should be within easy reach. Although I don't have a tt on my layout I can only imagine that this would be one place where things could go wrong, requiring the assistance of the Giant Five-fingered Crane. Your draft plans in Reply #23 and Reply #29 have the tt farther away than I would be comfortable with.
Again, just my $.02. Always remember Rule #1, but try not to build something that might disappoint you.