I have shot 75,000 frames in the past two years, and I would say under 2,000 with a 50mm lens... and probably around 50-60% with the 85... the 85mm f/1.8, even. I JUST got the f/1.4 about six weeks ago.
BUT, mileage will vary. I personally just don't like to shoot in "normal" range. I like wide and telephoto. There really is no great substitute for a 50mm prime when you need a mid-range focal length. I would say the argument should be 35 vs 50, not 50 vs 85. The 85 is definitely into telephoto range.
But you cannot look at the millimeter differences as totally finite. While on paper 35 to 50 is a difference of 15, and 50 to 85mm is a difference of 35... It's not the simple. The wider your lens is, the more substantial each millimeter becomes. 200mm and 210mm appear marginally different. But 14mm and 16mm are substantially different. So that 15mm between 35 and 50 is effectively larger than it appears. With that said, I don't think the 50mm is redundant in regards to 35mm. It definitely has a place. 50mm works better for portraits better than 35mm.
Also, just so you know, the 85mm f/1.8 is in a TOTALLY different build and quality class from the 50mm f/1.8. When you're climbing the tower of quality, it really is the gateway to pro-build lenses.
I think you should get the 85mm... but I'm not saying you should discount the 50mm in sake of it. While I don't like to shoot 50mm, I keep one in my bag at all times.