The attached line has us scratching our heads. The tentative plan is to use small-note symbol, coincidence signs on the "and" of 3, and commas to show the cross-beat 8th beaming of the large-print notes. If you've got a better approach to these measures, we sure would like to hear it.
But what about the order of the comma and coincidence signs when they occur together? I suppose it would be possible for multiple coincidence signs to occur within a comma-delineated group. Perhaps more importantly, the basis of the order of signs is that the closer you get to the note name, the more specific the signs are to that note. In my mind, the precise temporal location of the note is more specific than its relationship to the notes following it. So I would put the comma first in this situation. But there may be other ways of looking at it that I haven't thought of.
Start with the knowledge that I am not a pianist. I always try to show things in the simplest possible way, and what I think is simple sometimes does not seem so to a pianist. Here's how I would handle this passage, as long as it ts not a facsimile transcription. I went back to Appendix C of the old De Garmo for inspiration, but did not find an exactly parallel illustration.
Since the pianist is clearly not to wait until the end of the duration of the eighth note to start the "grace notes," I think an in-accord starting with a "grace-rest" is necessary. I'd show the opening eighth note and two dot-5 eighth rests in the first side of the I-A. In the second side, I'd show the grace-rest, the opening bracket slur and all of the grace notes. I'd use the measure-division sign to end that line (the RH part will be similarly divided, with an I-A. In the next parallel, I'd simply end the bracket slur after the eighth note A. I don't think any concidence signs are necessary. I really don't see any reason to show the beams across the beats except in a facsimile transcription. I'll try to attach a Brasille2000 copy.