Hi Lukas,
Massive disclaimer: I think I went through SE about a month ago. Impossible to know if that's accurate until I learn more. Mahasi recommends 2nd path+ before teaching and I'm definitely not that-- please take anything I write with appropriate grains of salt because I'm not at all confident. Here's where I think I recently was for context:
https://www.dharmaoverground.org/discussion/-/message_boards/message/16860231
So, your level of effort and dedication is fantastic! That's great and seems like a high percentage way to get to equanimity, but my experience was that equanimity through SE was incredibly tricky to navigate and no amount of effort alone could make it happen. The feeling of being fried and exhausted seems like what accompanies highly effortful practice and might be good signal for trying new stuff, it was for me.
I did some weird stuff that was helpful for reducing effort and ultimately beneficial. At one point I'd just note "striving, striving", or "effort, effort" or "forcing, forcing", and where these sensations were in the body, mostly in the eyes, face and guts. I'd also give myself cues, and just repeat key phrases like "still forest pool," to prime the brain to chill out a bit. See,
https://mctb.org/mctb2/table-of-contents/part-iv-insight/30-the-progress-of-insight/11-equanimity/ , namely the analogy of the kazoo player that suggests how noting can join up with the six sense doors. Gently investigate the 3Cs. Another good Ingram quote I'll paraphrase is that in earlier parts of the path we get conditioned that sensations like excitement, speed, blazingness, intentisty etc accompany progress because they do up to the A&P, and energy also accelerates through DfD and into Reobservation... but equanimity just isn't like that and doesn't crescendo in the same way. Another helpful analogy is the cycling analogy-- let yourself coast. "
However, Equanimity is like now coasting along on an easy, open, flat, straight road in a beautifully scenic area with no finish line to cross, no specific goal in mind, just effortlessly coasting and enjoying the scenery. If we employ a biking style from any earlier stage, such as totally powering it, as in the early stages, or if we are braking hard and swerving around imaginary obstacles, as in the Dark Night, we will likely miss the simple, easy, open beauty of the scenic area we have managed to get to after our long, hard ride, and instead just exhaust or frustrate ourselves instead of noticing what Equanimity is all about."
My (again low confidence) suggestion would be to feel really great about yourself for the striving you've done to get here, and make a formal resolution to chill out for some preset number of formal sitting hours, say 100 hours. If it doesn't work or nothing interesting happens, go back to trying hard. During this time use as little effort as possible. By this point your brain has sufficient experience noting the 3Cs that I think it's likely you'll continue to do so without effort. At first you might think this is totally weird and not meditating, and your sits will feel like cheating or something. I think just continue to let all of these emotions and thoughts and daydreams and pointless associations come up and do their thing and good things will eventually happen. If it helps, you can think of totally chilling out as a formal meditation technique that's appropriate for this part of the path. You then execute said technique by just sitting there. Try and be quite comfortable as well so that the body can also easily relax, I did a lot of reclining.
It was very hard for me to completely change my meditating methodology from maximum effort to minimum effort when I hit equanimity. I had developed a strong aversion for minimal effort because it seems dangerously close to pointlessly spinning in my stuff. But paradoxically, it works awesome during equanimity when the mind needs that. So, if you're fairly confident you're in equanimity (which seems very likely given your high dose of effortful practice), maybe give this a try. It takes awhile. Not really caring what happens seems to help. Good luck! Ben