Rain, could it also be some of the difficulty you are experiencing with your level 20 character (not necessarily your gladiator since that sounds particularly draining), is that you've hit your experience cap for the week? I'm pretty sure I heard that SE implemented a limit to the amount of exp/levels you can get in a set amount of time... so maybe it's not so much that you're having difficulty leveling but rather you've hit the cap and are trying to go up a harder current than the lower levels?
