The mighty Supercub I learned on didn't have rudder trim and that's 150hp in a relatively light airframe, didn't miss it and certainly didn't need it.
Neither did the Citabria in which I I did my TW endorsement. And that thing was twitchy!!
The Pawnee doesn't have rudder trim either, but I sometimes wish it did!!
PtP; 1400+hrs Glider towing in Pawnees.