Here's some interesting ideas.(I know it may not be very likely, but who knows. People are making a lot of mods of SRB2.
)
Freeze-Ring: Moves slower than a normal ring, but if it hits, the target will freeze on the spot for about... 5 seconds sounds good. Perhaps even a console option to change how long they freeze...
Ring of Doom: Very hard to get, and has a 10-second duration, but causes instant death to those who get hit by it. Moves at the speed of a normal ring.
Force Ring: If it hits, the target will be launched away. Slightly faster than a normal ring. It also slightly pushes away all players it passes. In CTF, if you hit an ally with it, it won't cause him to drop his rings, but it will blow him quite a distance.
Big Ring: A big ring... Big rings mean more accuracy.
Slightly longer attack delay.
Boomerang Rings: Comes back to the shooter when shot. Does not come back if it hits something. Like a player. It's like a second-chance thing. Slightly longer attack delay.
Spring Rings: Like the Force ring, except it launches the opponent upwards. (Imagine having a ceiling that does damage. ;) ) (Might also be handy for CTF if you hit an ally with it.)
There ya go. my thoughts. Feel free to be disturbed by them. ^_^