Like Nepene said, head to the fjords (from the path to the far south west in Broken Valley) and you can level up fairly quickly (easier as a mage or ranger).
Are you summoning your creature for help (or at least a distraction)? A few stat or armour boost potions might help, and hit an run tactics should allow you to whittle down the number of bandits, etc.
You will need to finish off most quests in Broken Valley and Sentinel Island soon anyway, so you could go do anything that you have left (entering the quarry tower can wait until later, as can retrieving the treasure from the boat in the tree).
There was a respawn point in Maxos temple, in the mirror room. In the kind of room section straight in from the entrance, on the right after the half height wall, there is an empty barrel that spawns 3 opponents each time you open it (you can do so multiple times and then fight them in groups; exploding arrows works well there). The mirror room remains accessible for awhile, but the barrel stops spawning opponents after you complete the 3 tests and move on in the temple.
Welcome to the forum.
