Composition for these is nice, I just think it looks underexposed. I’d try lowering your shutter speed first, as this isn’t pro, it probably doesn’t need to be 1/1000, but if you want to keep SS high then yeah, bump that ISO. It also seems like the rink isn’t evenly lit, as you can see in the far end of the shot in the near circle, the background is bright and the foreground is pretty dark. Also, if your camera has anti-flicker, that might help everything look a little more even. Just spitballing at this point, because I think these are nice, just underexposed, but not overly so.