Dear Koulouf,
Your series of 1-5 contexts looks sound - but, yes, you could also manage a context to pair with your 'Strict muscle-up', either focusing also on capacity-development or, as you mention, work on "softer" qualities, such as coordination. For the latter, the 'Tennis-ball foot-dribbling' project would be a good pair as it focuses on the other end of your chain (i.e. legs, rather than arms), and allows for quality rest. This could be for just 1-2' practice between sets of muscle-ups: https://www.movemorevrl.com/projects-tasks-timing-rhythm-and-coordination/videos/tennis-ball-foot-dribbling-1
You could, however, also pair with an OVERHEAD vertical-pushing context (e.g. 'Pike-pushup' or 'Bent-arm stand' development, on floor, elevated, or on rings) if you wanted to keep things purely upper-body. But you would just have to be mindful of fatigue here taking perhaps 90-120" rest between sets. If it's a more general bodyweight session, you could likewise work on some aspects of bodyweight, lower-body development.
For the elbows at ring-lockout, whilst the best practice will be the context itself, as it is not a technical/skill-oriented one, you could also include more "stable" variations of support forms (such as 'P-bar pike-extensions', or even 'Floor/bars L-sit) in your training - you might even switch this for the 'Fundamental ring-support' in your program, because you will be doing this anyway in the final position of your 'Muscle-up'. On more stable surface (e.g. floor/p-bars), you are able to hold for longer and this will develop both greater neuromuscular-efficiency (i.e. the pattern of end-range "lockout") as well as conditioning the elbows.
If making this switch, you could then practice the 'Ring support' on a DIFFERENT day - even as part of a more frequent 'Priority' practice - for just 1-2 'dropsets' (DS) 3-5x per week. I would generally just look to accumulate up toward 30" of TUT (time under tension) per 'visit', e.g. a dropset of 12", 10", 8" with minimal rest, or just 2x 'reps' of 15" holds. This low volume, but higher frequency, I would argue is a more sustainable structure for developing joint-integrity (we are, after all, concerning ourselves more with PREHAB when it comes to developing elbow-lockout).
2x sessions per week with your MU session as it looks here would be fine. I don't think 3x would be necessary. My advice is to keep it up for at a least 1x phase of 6-8 weeks practice, reflect afterward with regard to how the joints are feeling, how sustainable the practice is, and your progress, then adjust if necessary.
R.e. apparent unilateral imbalances between sides, you are doing the right things already to attend to them - that is, firstly NOTICING (you will then have more awareness and therefore improved attention to them in practice, such as if there is suboptimal patterning in scapular-activation), and secondly investment in UNILATERAL contexts to attend specifically to them. These things generally tend to "iron out" over time.
Lastly, and more general toward your objective of 5x 'strict' MU, also ensure that you can achieve (and, if you can, maintain it) 5x 'strict' ring-pullups with a 1" TTC isometric hold on each rep. This will ensure "unified" strength in the pulling chain into its very en d-range, make the transition on each rep easier. Lastly, execution-wise, do make use of the ECCENTRIC phase of the transition, if you're working singles. Keeping the chest HIGH and looking toward maintaining TTC from the bottom of the 'Dip' all the way to to the top of the 'False-grip pullup' will, again, help to "fill" any strength-gaps in this chain of patterning, which is generally the crux of the MU.
Let me know how it goes - wishing you strength & ongoing progress!
Jason
