I don't know if it would be useful for normal mode run, but charged Knuckle is your friend, really. You can hit with it few times, like with aerial saber slash, but... there is NO 3 frames of lag during each hit ^_^ Useful for fighting with those three dragons for example.
And on Icy level (hibernation chamber) taking upper path with taking claw weapon would be nice idea when you have double jump. (You chose "hidden" lower path in published movie, thanks for showing that way ^__^) You can get CLAW there, then move one level down on elevator, make it move upwards and fall down - I did it with killing enemies on every floor during falling and got to the midboss only ~1 second later. If you just fall without slowing down to kill enemies, it will be faster. Also I killed midboss with claw faster then you in your published movie, using turning to do multiple hits and double jump to stay in air, I killed left part of it with one big jump, and finished all the other parts with another jump. You can take a look at it here: (just fast-forward through first few levels to frame 33800, they are really unoptimized, it's not my current wip, but in current run it's only next level for me, so it's not redone)
http://dehacked.2y.net/microstorage.php/info/2937/MMZ4_4_sakura.vbm
And don't forget to skip "Inticreates" screen using start+select+A+B (if you did not - you can hex edit it, it wont affect anything luck-related)
By the way I would like to know if my hard mode run WIP (in corresponding thread, not one in this post) looks much worse than your current work ) I think I tried hard~
