Fantastic project.
We are very exited about the EASA STC...
Did you consider the 5-blade MT propeller for the project?
https://www.mt-propeller.com/en/entw/stcs/beech_ka90_2.htm
https://www.mt-propeller.com/en/entw/stcs/cessna_206_3.htm
Would provide some extra ground clearance and cooler starts.
(and a fair amount of badassness)
cheers
Jakob