Re: Poo AND detergent smell ugh!!!
If you are washing that many diapers, of types that have a lot of layers, you definitely need to prerinse. There is no detergent that is going to get you out of that. You just have too much crud for the detergent to deal with.
It's interesting that you say the Tide Original got rid of the smell "for the most part" ... meaning it really didn't. You either aren't using enough or it's not right for you. I personally hate Tide and like Country Save but I get that it works for a lot of people.
I used flats at a laundromat situation and still always ran 2 cycles. I'd usually run one full cycle on cold, then a second with detergent on hot.
-- Rinse, one way or another. Try a diaper sprayer on the toilet, rinse right when the diaper comes off. Or start running 2 cycles.
-- Use Tide Free & Clear plus some Washing Soda.
-- Run smaller loads, wash every 2 days.
You might look into buying a Haier HLP21N. I got one from Home Depot for $200 delivered. It's a huge purchase but it will save you a lot on laundry. Just as diapers are a big investment up front, that saves you a lot in the long run ...