Here's a couple pennies worth:
If shot in RAW, in PPing you should be able to designate WHATEVER white balance you want. Shot "indoors with auto WB", just change it to Tungsten light or whatever looks proper to you in PP. I wouldn't worry about uniform color...skin tones showing properly is what you want here... Then, you'll need to adjust the levels for a full histogram, which lets you set what should be pure white and pure black. There's many ways to do this, but that's what will clean up your uniform colors. Adjusting the contrast will give the photo some pop.
You are at the limits of that camera/lens combo for the type of shooting you're doing, but there are some other things you can do without spending lots of money (I'd say getting a more modern body will aid significantly though). Your Tokina is a slow zoom, so it's good you tried the M50/1.7. But you can get more out of the lens than you are. f/2.2-2.4 should be plenty sharp, while enabling you to isolate your subject and gain a little in shutter speed. Most pro shooters for sports will use a fairly open aperture for just that reason. Of course, they're using top dollar AF lenses, and you're trying with MF lenses. So...learn about hyperfocal lengths. You set the lens and then don't touch the focus. Ever hear the phrase "f/8 and be there"? There's also "catch-in-focus" (where the shutter won't fire unless the subject is in focus), but I'm not sure if the istD can do that.
Panning helps. So does rotating the camera into portrait mode vs shooting everything in landscape and then cropping to portrait, (leads to less noise since it effectively give you more megapixels for the frame in question). Finally, you might consider getting a 135/2.8, or maybe a 105/2.8. The 135 might be easier to find since it was such a popular focal length on film cameras (it might bring things a little too close in a gym setting though, hence the search for an 85 - 105). Since it's a prime, and everyone made them, you can find that "most" examples will be sharp enough even wide open. Spot or center weighted metering can also gain you a little fast shutter. Then, shoot, shoot and shoot some more. Lastly, as someone's already mentioned, converting to B/W using software and "filters" can brighten up the shot and make the grain look more appealing.
Not quite the same environment, but here's a couple taken with a Soligor 135/2.8 on a K20D at a night football game. IIRC, these were shot wide open and cropped to bring the action closer.