The wings and its components are maybe the most important parts of an aircraft, so why not improve them a little!
Flaperons are control surfaces located usually between the inboard and outboard flaps which combine both flaps and ailerons.
Roll spoilers is the movement of the spoilers which helps the bank of the aircraft.
Currently flaperons are correctly working only on the Boeing 747-400, and the only aircraft with roll spoilers is the Cessna 208.
My suggestion: add working flaperons on the Boeing 747-8, Boeing 767-300 and the 777s, and add roll spoilers for all aircrafts.