Cool! Awesome goals to have! Crits are a ton of fun and pretty humbling. LOL.
Have you raced much before? what is your history riding a bike prior to this year? (I’m going to assume not a ton of experience given the way you talk about cycling) The reason I ask is that while, yeah, everyone TR talks about power on the bike for racing, I’d probably say bike handling and being in a tight pack is pretty important in racing. This is not something you’re going to learn while sitting on a trainer.
Not sure where you live and whether it’s a deep winter place or not, but I would recommend you ride outside more vs the trainer. I would configure my bike EXACTLY how I’d want to race it and gain a comfort level with my setup so I know how my bike will react under a broad set of conditions. Also you have chances to ride in groups as well to learn pack handling skills.
The other benefit of riding outside is that you get to explore your local area pretty well and find a lot of cool spots out there. Running always seemed pretty boring to me as you could only go within a 5-10 mile radius somewhere. You can actually get somewhere on a bike.
Bottom line, tho - sounds like you have an engine, you’re right that your muscles just need to catch up to your aerobic capacity. have fun out there!