Priority 1 is getting a speed campaign farmer. Kreela can't really do that. Fellhound is a good choice - for campaign farming. But he's 100% useless elsewhere - and priority 2 is getting a Dragon 20 team. So, in an ideal world, you'd pick someone who can do both.
Sadly, from what I can tell, I don't think you have anyone that fits that bill. So, for now, you run Kreela as your campaign farmer to level food, I suppose. Are you able to clear Brutal 12-3 with her? If so, I think you just hold your nose and continue using her to farm the rest of your food, and get your Dragon 20 team together, and see if you get anyone else in the interim.
For Dragon 20, I think you want:
- Kreela (AA)
- Genbo (Wave Clear)
- Jorrg (Buffs, Backup Revive)
- Bystophus (Debuffs)
- Mushroom Dude (forget his name) (Support buffs + Poisons)