I think you did a great job of capturing key action points and getting in close, although some of them are either shot or cropped above the ankles and I find that to be a bit of an odd place to stop. I would either go for waist up, or include the feet (but that could just be me). The colors look good, but the images are overall too dark IMO. The first thing I thought of when I looked at them was confirmed when I read your sig, they were likely shot with a 2.8 lens. While it's a fantastic lens, IMO 2.8 just doesn't cut it for fast indoor sports. It seems the 85mm 1.8 is the "magic lens" for volleyball as you are already contemplating. That might be just the ticket here, but not so sure for basketball. I typically shoot from under the basket with a 50mm and it's just about right. I think 85mm would be too tight in that situation if you are expecting to catch drives right up to the net. I started out with the Thrify Fify for about $75, so if you do find 85mm to be too tight, it's not that big of an additional investment. I've since moved on to the 50mm 1.4 and have found it to be marginally better for basketball but I'm not sure if it was worth the additional $$ just yet.
Canon 30D, Canon 50mm f1.4, Tamron 28-75 XR DI f2.8, Lowepro Micro Trekker 200, Cheap Promaster Monopod
Next planned purchase - Canon 135mm f2L