I once saw a level 18 Pure fighter do the swim on Elite.
This quest is meant for, "Mario Brother", type reflexes and of course Evasion helps, but is not needed.
But without evasion I personally could not do the swim.
Rogues, Rangers, Aritficers, Monks, Druids, Fighters, Clerics, Favored Soul in my opinion, can make specialized builds to do it with ease.
Can we get a bump in the xp at the end of this quest to keep it a viable quest to run?
Or how about an extra chest at the end?
Or make it a Raid?