All of my engines over 50 cc have as a factory setup ---
a large central, flanged prop locating, shaft (10mm) with locking nuts, drilled for 5mm spinner attaching bolt.
Six, clamping bolts - in 4mm and in 5mm dia. , sizes
Kept tight - is a very good setup.
Honestly -I can't think of a better one.
This sounds a lot like the setup just described.