Welcome to the forum!
I upgraded to a 7D a mere four months after starting with an XTi. (400D) I was being mentored by my wife, and was handling and shooting with her work camera, a Nikon D300s, which is the Nikon equivalent, more or less, of the 7D. I do not believe either of these excellent cameras is too much for a beginner. If you have large hands, this is all the more so. The 7D does demand that one be a serious beginner, but is actually quite user-friendly, in mu opinion.
Canon 7D2/7D/5D/40D/1D2N/M3; Nikon F6/D700/FM3A/1Dx/Coolpix A; Canon 40mm 2.8 STM, 135L, 50L, 35L, 50mm 1.8 I, 100mm 2.8L Macro, 10-22mm EF-S, 400mm 5.6L, 16-35mm 2.8L II; Nikkor 50mm 1.2 AI-S, 50mm 1.4G, 50mm 1.8D, 16mm 2.8D Fisheye, 180mm 2.8D, 100-300mm 5.6 AI-S, 45mm 2.8 AI-P, 14-24mm 2.8G, 24-70mm 2.8G, Micro-Nikkor 60/2.8G; Voigtlander 90mm f/3.5 SL II, Zeiss ZF.2 2/135 APO