00:51:995 (216,217) - I think making here mono is not a good idea, since the pitch is changing. You could consider change this note to kat
01:04:095 (284) & 01:10:495 (327) & 02:16:095 (691) & 02:22:495 (734) - change to don for the same reason
02:56:495-02:58:095 : These 1/8 doublets are really cool! But seems easy to catch the player off-guard, since they're a bit tricky and introduced so suddenly. It could be worth making these mono-color, and I think it would still fully represent the part.
So maybe:
...or something
Also maybe worth omitting 02:56:895 to bring the focus more to the guitar rhythm.
Or do whatever works to just make this a bit easier, since it just sticks out compared to the average difficulty of the rest of this map imo. Like applying these suggestions actually brings the local SR from 4.21* to 4.15* alone which kinda shows how spikey it now.
03:27:295 (210) - could change the note to Don to emphasize the special sound at 03:26:895 (209) -