Recommendations for better brakes.

My SJ has a 19" spoked front built from a Mikes XS flangeless alloy rim & stainless spokes, plus an EBC rotor and 11mm m/c. Braided hose, of course.
I had a heartstopper recently when some idiot was driving their BMW SUV on my side of the road (!) so I've decided on a further brake upgrade; I have the Pandemonium kit ordered and a 65mm Brembo Goldline caliper is in the post.

Has anyone tried an 11mm m/c with the Brembo 4-pot caliper? I'm wondering if 11mm might be a tad too small, and maybe I should look for a 12mm m/c?
My machine has a Nissin MC mated to a Brembo Calliper & front rotor; It is very powerful and wonderfully controllable.
OK I have a Ducati front end on this but I'm sure the creatives could fashion a similar set up to fit the XS.

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