Now that I have played through a fourth time and really wanted to focus and power level my last run through I tested out all the places to grind out exp and power level.
The best place by far is level 6.
There are 3 respawning skeletons at approx. 45 seconds each, 2 respawning snails at approx. the same 45 seconds. Then there is a respawning crab which I would say is around 5 to 6 minute respawn and the 3 fire elementals at 5 minute respawn.
3 laps of skeletons, with a snail run when entering and leaving and then to the fire elementals and then back to the snail and skeletons.
In total for a full run through elementals crab and skeletons and snails the exp is 3000. Much higher than any respawning area in the game including the ice lizards.
With the snail food drops it is a infinite exp loop if you have the patience.
Really the only viable way to have a capped 50 score on an ability before reaching the end game.
All of them are triggered by stepping on a specific tile.
By the time I was done with skeletons and a level of 15 the area was completely covered in shields...
Anyway I thought I would share this info for those of you who want to level some skills to 50 before really near the end battle.
I can map it up if any are interested.