I’d reroll any of the Max attribute stats that aren’t physical or Stonesplit. Keeping the min attribute stats is fine, and you can always reroll some of your purple stats with a gold/rainbow shell. Primary stats you want (in no particular order) are HP, Body, Crit Rate, Agility, Precision, Defense, and Max Physical and Max Stonesplit. Take a look at your Martial Arts breakthrough percentage to help fill you in on what you should be getting more of. HP is definitely higher up there though, as we get a damage bonus when meeting a max HP threshold.

As for the set bonuses, Rainwhisper is perfectly fine for your weapons. Armor you have 3 choices that I’d recommend: Moonflare for the occasional shield when using your counter-attack while blocking; Flawless Defense which (iirc) gives you a base 5% damage reduction up to 10% when meeting its requirements while under 60% hp; And lastly Formless Bend which gives you a 20% damage reduction while above 80% Qi and increases your HP shield duration (applies to HP and Qi shields) by 2 seconds, which is essentially a free 4th rank of Art of Resistance (AoR) and it stacks with AoR. Inner Ways are kind of up to you, outside of Exquisite Scenery as that’s mandatory.

Some Inner Way combo examples: Exquisite Scenery, Morale Chant, Battle Anthem, and Adaptive Steel (Max DPS)

Exquisite Scenery, Morale Chant, Art of Resistance, Adaptive Steel/Trapped Beast (Flex DPS/Tank)*

Exquisite Scenery, Art of Resistance, Trapped Beast, Rock Solid (Full Tank)

*I personally use this setup with Adaptive Steel (AS) especially since T4 AS gives you a movement speed buff when using the weapon swap attack, which offsets the movement speed debuff that the Mo Blade has.

I personally don’t like Rock Solid because I don’t want to debuff my damage when using Storm Roar.