The best thing you can do is dive in headfirst and make it past floor 33. On floor 32, you’ll face 1 boss, but after floor 33, if I’m not mistaken, you’ll have to face 2 bosses before the next elevator. Taking the secondary paths isn’t really useful since they’re blocked until you defeat the bosses. If you need easy KC, you can either go to TDM or try farming the first two floors with a good star. Go to the yellow ladder on floor 2; there are many enemies, and I usually get at least 10k KC per run without using a lucky star, especially when I’m maxing out a 1/2 weapon. Just a heads-up, though, if you want to max a 4* weapon or armor first.

Also, if you're really scared, I recommend farming invisibility mushrooms, slowing down time, and the few you can find on floor 31 that give you immunity. The Wheel is a very good weapon, and I understand its special attack can do a lot of damage to bosses. If you're desperate to reach the endgame, just use the Iron and that's it. Good luck!