Ah, Vitty...how long has it been...
First of all, here is a suggestion: instead of using Martial Arts as a weapon, I'd rather put the use of a SPECIFIC MARTIAL ART as requirement. If you choose fighting actively using (for instance) Base Shadus as a requirement I'd treat it as a -5MK disadvantage. If you set necessity for using Arcane Shadus, the MK reduction should increase to -10MK. I'd personally stick to Base Shadus for all techniques (including the Armor) except the Level3 technique, which should require Arcane Shadus.
Sword
I'd go for a final ki cost of Dex4/Pow4/Wil4, so that with Base stats at 10 on the three used characteristics, you require only 2 turns to pull it out.
Buzzsaw
Again, I'd go for final ki cost of Dex4/Pow4/Wil4.
Rapier
I'd rather add a -1Ki cost for a final ki cost of Dex9/Pow9/Wil9 and MK cost of 50.
Shadow Armor
Since I'd add the Shadus Martial Art requirement here too, the MK cost would drop to 60.
Black Wing
On my calculations, you can achieve Dex9/Pow9/Wil9 buying just -1Ki. Also, I'd use ARCANE Shadus Martial Art requirement for this one, so the final MK cost would be just 65 (which is just enough for a Level3 technique, anyway.
All in all, this school is very cheap both regarding MK and Ki, so I sincerely like it very much.
Be sure I'll be waiting for the Light Disciplines!