Overall not a bad kit design. Thou I do have a few problems with it. 3 to be precise.
The first is, as stated before, Shatterpoint being placed on a random enemy. It has the same problem as his current Expose. It makes it really unlikely that he ever triggers it due to Stealth and Taunt existing. And no, him not being an attacker is no excuse for this. As you could also easily not make the Shatterpoint bonusses do something different than extra damage under the same reasoning.
The second is much more significant thou. It has to do with the Jedi Champion unique, as it's way to powerful. Think about it: If you have JMK lead with KI-Adi-Mundi and this Mace Windu, all GLJ allies have + 90 speed and + 105% Max Heath, while supports/healers gain offence equal to 10% of their max health and tanks gain defense equal to 10% of their Max Health (which with 105% increase is basically at GL level. Your supporters will likely deal more damage than JMK and your tanks will basically take no damage at all, even against high Defense Penetration characters). That's way too overpowered. That's what happens when you copy an end-game TB character's arguably strongest ability an allow it to stack with said ability and a leadership ability: It tends to get out of hand rather quickly.
p.s. JMK lead allows tank allies to regain taunt when they lose it if they have protection, so the taunt while he had protection up clause is a bit useless as well. Since he was meant for that team.
The last has to do with inflicting the opposite debuffs for his Smite Specials. It does mean you will need to mod him for Potency a bit now. That just bothers me personally. Thou it isn't exactly bad either.
Overall a good kit thou. Just has a few problems that need to be fixed. I did a rework idea for Mace Windu myself quite a while back. You can find it here, if you're interested:
https://forums.galaxy-of-heroes.starwars.ea.com/discussion/228230/mace-windu-rework-idea-galactic-republic-jedi