Honestly, I can be VERY overwhelming. We are preparing for our 4th cruise and I am always overwhelmed. This is a great place to start finding answers/ideas.
I only JUST bought magnetic hooks for this upcoming cruise. There are tons of ideas for using them. For me, it's a place to hang extra things I don't want on the floor or on the desk...like lanyards with our sea passes, using them as just magnets for the daily cruise compass or other paper items we want to be able to see/access, swimsuits off the floor, towels off the floor.
I think most things like the trivias, etc. from what I've read here might take 45 minutes to an hour or so. Someone else will chime in here who has more experience with those.
The compass can also be overwhelming, but so helpful. Just find one that is a similar itinerary as yours and just familiarize yourself with wording/times/venues/etc, then don't worry about it too much more. It was so helpful for me to see one before our cruise so I felt like I had more of an idea of those things so it WASN'T as overwhelming as it would have been if I had just showed up onboard and gotten this gigantic document.
What ship are you sailing on? On each of our cruises, I've been able to find quiet spots to relax/get away from crowds. I struggle with some crowd anxiety, non-medicated, but I can get to the point where I just need to GET OUTTA THERE. It's helpful that we cruise in balcony rooms for times when I just need a quick getaway.
We have been to Cozumel twice and I love it. I might be in the minority. I enjoy walking around town (after taking a taxi). We have eaten at 2 different restaurants and shopped. But we've not done a paid excursion.
You have enough time to do your research to get comfy with your ship/ports and have questions answered. Make sure you keep up with this site. DON'T join any FB groups. They are full of drama and people not giving sound advice (IMO).