I just have a lidded seagrass basket beside the toilet. Not airtight or anything, it even has holes in the side for handles. Absolutely zero smell. I use it for fc but also for mama cloth -- unrinsed mama cloth, just straight from my undies into the basket! No smell at all.
It's a different story with cloth diapers, I guess, and maybe if there's a lot of #2 on your family cloth. But ours is filled with pee and blood and we've never had any smell problems. No wet pail, no essential oils, no baking soda, just a basket.
Heather, mom to Caileigh 12/06 and aspie ADHD prodigy David 05/98 :intact lact