This could have great potential. But, if the entire level is just the rink, the map will suck, badly. Besides there is already one like that I think. However, if you have the rink as the center of the map and add the tunnels, locker rooms, etc., it could turn out good. It could even support ALL game modes. Imagine this:
1-Flag CtF- Flag in the center of the rink, bases are in the locker rooms.
Ctf- flags are in the locker rooms. Naturally there will be back doors through a bathroom or ventilation system or something.
Pong- everyone spawns in the middle, hits the ball/puck in the goal. Walls blocking the exits to the rink with "gamemode 64" set somehow.
KotH- The rink is the hill.
Siege- the rink/stands are the base with a flag somewhere.
Elim- the second easiest game mode. Team spawns.
DM- The easiest game mode. Random spawns around the arena.
But like I said. Great potential, if done right.