Diablo III is really accessible. If you've played Torchlight you're fine.
Although, playing the XBox One version? I know people like the console versions (djpretzel loves the PS4 version), but I've gotta say if you're gonna play D3, join us and play on PC. That's where most of OCR's players are playing, and that's where the game is most up-to-date.
Here's the "Starter Edition" where you can try the game out on PC.