I worry that focusing on the USMLE will negatively affect the COMLEX, since I plan to apply AOA that's the exam they're more concerned with. Is that not something I should worry about?
In my experience, and by what I've gathered from fellow students that scored 240+/600+, that is completely false. I actually think it's the complete opposite. Aside from the impressively poorer quality of comlex vignettes, the only real difference is OMM. My hardest biochem questions were on comlex and I walked away feeling like comlex was more difficult.
The bottom line is, if you know the material, you'll do well on both exams. I HIGHLY recommend using USMLE resources: First Aid, Pathoma, and UWorld. Combank is subpar in every aspect. The grammar is awful, it's riddled with errors, and the explanations are not as detailed or helpful compared to UWorld. You cannot "get use" to oddball comlex questions... their stupid questions will always be vague, nonsensical, and frustrating.
I do suggest taking COMSAE exams, reading Savarese green book, and knowing OMM well. Seeing the differences in format and timing is worth it. Don't sell yourself short... you have 1 opportunity to do this right and it will impact your career path forever. Unlike other jobs, once you're in a specialty/program you are there... there's no switching industries, etc. The residency merger only further reinforces why you should take the usmle.
Regardless of what you hear, the usmle is the gold standard test. Even if an acgme program accepts comlex, it is better to have a solid usmle score to show with it. I'm almost 100% only applying AOA and preparing to take the usmle from day 1 is why I got a 2+ standard dev score on comlex and have the confidence that my board scores won't hold me back for anywhere I apply. Do the same!