Hello! I've been lurking here a while, haven't posted before now, but this is the first time I feel like I might have a perspective to contribute since I think we're on similar journeys!
I started piano just over two years ago, went through most of Adult Piano Adventures 1 by myself, and then started lessons with a teacher, where I played through the children's versions of Piano Adventures 2a/2b/3. My teacher then suggested that we work through RCM starting with Level 1. He mentioned that he doesn't do RCM with all of his students, but that it's good for those who are very dedicated. This gave me pause (am I really dedicated enough?) but I decided to go ahead with it.
I went through levels 1-3, typically playing double (or more) the amount of required pieces before moving on to the next level. I found the increase in difficulty to be very gradual from Level 1-3. In fact, there's one piece in Level 1 I played (Cranky Cat 😭😭) that I would consider much harder than anything I played in Level 2. So I definitely think you could jump into Level 2 if your teacher is so inclined.
I decided against doing exams for levels 1-3, but I did end up doing one for Level 4. Like you, the motivational aspect of the exam doesn't really do much for me, but since I was moving through the levels very quickly, I started to doubt my skills and whether I was actually achieving the level I should be, or if my teacher was just being nice.
So I took the Level 4 exam to, in a sense, get a second opinion. And I did well! 😅 So if you're like me, prone to bouts of imposter syndrome, it could be worthwhile to prepare for the odd exam to have that confirmation. I still think I might be an imposter, but at least I'm a pretty good imposter. I did do the exam online, because I was terrified of playing any other piano than my own.
I probably won't take another exam any time soon. Preparing took a lot of time to perfect the pieces, and in this time I didn't feel like my skills were improving much. I've now just finished Level 5 and have started on Level 6. Things are getting really difficult now and I will certainly have to slow down a lot. Possibly I'll do the level 6 exam a year from now, I don't know!
If you do skip directly to Level 2 pieces, I would recommend not skipping the musicianship and technical requirements for Level 1, as each level has a different set of scales, etc. to learn, if you skip a level, you may not come back to that key for quite a few levels. The musicianship also builds on what you learned in the previous level, and at least for me, took the longest to build up skill in.
Looking forward to seeing which pieces you select!