Lvl 30-35 is one of the hardest lvling spots. I was surprised myself at how slow that took. Anyways, here's my suggestions.

33-35: I did trixsters here. I found this perfect spot on floor 71 where you get 2 yellows and one green. As you don't need HP pots, you can spend your cash on MP pots and PS all the time. Not great exp, but good exp for this lvl.

35-40: Do a couple pqs here and there, seeing as you might want some of the prizes(got myself skull earrings, blue moon, and anapolean cape outta lubid pq. Also made 100K one pq), but mostly do cats. I find that I can get 3% every 5 minutes at cats. Now I'm not saying I like the cats, I'm just saying that they're good exp for this lvl. The drops are also sweetness on the red ones, seeing as they can drop some good items for warriors. I'm still trying to get those blood battle grieves to drop though. For sword users, party up with some higher lvls, and go kill the big red cats. There's a small chance that they might drop a zard. Once you get your zard, stay for as long as you need, then go back to small cats until 40.

Wow thats a long 35-40 post. Anyways, that's all I have to say.