Thanks so much!!
In the fall, our class schedules were usually from 10am - 3pm, M-F. We had mandatory TBL (team based learning) maybe every 2-3 weeks which consisted of mostly biochem quizzes. The last 3 weeks of the fall semester had more mandatory classes because we had integrative TBL sessions, research group work, and journal club presentations. Exams in the fall were every 4 weeks. Yes, most of the lectures are optional and I know that several of my classmates never showed up unless it was mandatory or an exam day. If I noticed, I'm sure the instructors noticed too. I don't think it will necessarily hurt you, but I will say that when it comes to TUCOM admissions, I heard that instructors provide commentary on the students that they want to recommend for admissions, so keep that in mind.
Also, I saw that you mentioned working in a previous post. I know a few people who did work and it's really tough. I'm sure they met the minimum cutoff, but I don't think they performed as well as they would have liked. They made it work though - kudos to them! I did the program as a parent of an infant and that was a full time job in itself, but it was possible.
As for in person activities, I went to campus a few times. A group of us asked to visit the anatomy lab to study the brains for neuroscience and the cadavers in anatomy during the spring. There were also a few osteopathic activities at the OMM lab that I participated in. I honestly loved doing the program remote because it was just easier to roll out of bed and sign onto zoom for class right before start time lol. If you have a 490 MCAT minimum, then TUCOM will focus solely on your performance in the masters program as long as you meet the 3.0 gpa or get an 80% overall. I had a 496 MCAT after 3 attempts and finished the masters with a 3.55 (Finished undergrad with a 2.60 gpa, and 2.4 science gpa). It wasn't easy, but it was very doable, and I feel like the exams are suuuuper fair.
Let me know if you have any other questions! I was lurking through the thread last year looking for answers, so I wanna provide as much help as I can!