CapnZapp
Legend
At the absolute minimum it needs synergy between its signature attack (the radiant 30 ft attack) and the reason you're a monk: delivering stunning strikes.What are the flaws?
The best suggestion I've seen is to let the Sun Monk spend a point of Ki to make its ranged attack a Blinding Strike, just as every monk can spend a Ki point to make a Stunning Strike in melee.
But has the subclass changed since SCAG? Nope

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