You can, lots of engineering work in 50-70’s with bleed air thru ducts (leading or trailing edges/ Coanda) penalty is structural complexity, maint headaches to maintain clean ducts and consequences of engine loss when below unblown stall speed. Engines exhausting across wing are less complex, but there’s cruise drag penalty and skins take a beating. This concept is potentially draggy in cruise but given limited speed range/priorities of a Cub is comparatively “simple” if you discount the wiring/mounts. Cub solution compared to exotic concepts kind of like fixed gear vs retracts, in slower aircraft fixed gear reduced weight (less induced drag)/simplicity beats out more complex retract’s reduction in form drag.
For laminar flow comment, high AOA is about maintaining boundary layer attachment, laminar boundary layers separate sooner than turbulent flow (dimples on golf balls). Laminar also more demanding of production/maint/contamination
(bugs/rain).