I don't think channel duration is the answer, mainly since Teleport is in a good spot when its only being taken by the top laner, my problems with Teleport is double teleport. I think the solution would be when Teleport is used it will place all other Teleports on THAT team on cooldown for ~120 seconds (placeholder value). This would prevent two champions show up on one ward or minion from across the map and not hurt Top lane's team play and actually participating in the game because I don't want top lane to go back to snowballing island of isolation.
I am also going to suggest a new summoner spell which will be similar to teleport but strictly about lane recovery only. Here is an example:
> **Return:** Cooldown: 210 seconds
> Channel for 4 seconds and upon completion return to the location of your most recent successful recall.
_A summoner spell like this would be cool to have as it offers someone against a tough match up to try to get back into the game rather than have to nerf early game lane bullies to the ground because they snuff out any other champions from getting played. This would grant mid-laners a spell for lane recovery and not have the obnoxiousness of double teleport comps which double TP really shuts down a lot of strategies where as only the top laner having teleport keeps other strategies open._