Great start and IPM. Gonna pick your brain a minute.

Other than the gnats and nematodes/sticky traps, what other pest and solution should I expect to encounter in an indoor grow in Michigan/Midwest area.
Outdoors I use insecticidal soap on aphids if I can't wait for the ladybugs to show. But how do you spray in a tent? Or do you take the pots out and spray then put them back?
My system uses a 3 barrier system as follows
Outer barrier is outside of the grow room. It includes 2 " honey " traps with stuff any self respecting bug would love. Apple slices dirt and kept moist. After 2 days if you bump the 2 gallon plastic bucket a swarm comes out and is everything under the sun. Flies, earwigs, gnants, ants, even a cricket. Every 2 days I put a top on the bucket to take outside and clean the bucket. When cold I nuke it with defender and pour it down the sink.
Closer to the room is a self closing door hinge and a rubber strip on the bottom of the door to reduce airflow into the room. Study showed flying insects use air currents to find pathways into closed areas. I also use defender on the baseboards in the room and on the carpet. This stuff is pet friendly and lasts the whole grow.
Inner barrier is every hole in tent carrying airflow is on an insect screen and of course sticky traps in pots.
I have also as of last grow started to take a group picture of the sticky traps and blow them up with zoom. I did this after a guy who had spider mites showed 2 pics one normal and one zoomed in. There is a stage in spider mite life cycle that you can not see with eyeballs alone unless you have robot eyes or something. I have never had spider mites.
I wanna keep it that way.
Chemicals are limited. I am not/never going to spray a flower and then wash it to smoke. Sounds iffy and dangerous. I have used
neem oil as a drench in the pot and I recommend this at minimum 3 weeks above ground as the excess water at sprout has a high mortality rate but it does work and with one application.
I also use the glowing blue sticky traps several places in the house. The gnants this year were the worst ever and the cats bring em in. I am pretty sure the gnants this year came from a bag of
happy frog. And the way it happened was obvious after the fact. The bag was prolly one of the last ones on a pallet that prolly held 100 bags and it had been sitting a while is my guess. It was not wet and it was not ripped but even so I got bugged.
The active running tent for 7 days will hopefully end the Gnant issue
Hope that helps.