"oleos" will contribute to ground resonance. It's a constant consideration on the 269 and has been since 64' when the U.S Army started buying them.
If the Thrust Control Rod was not down in it's proper position in a CH-47 with non-proportional ECLs before going to flight with the ECLs, and a strut was not properly serviced, you could get a real ride till the blades got in sync.
A wheeled aircraft in rough enough terrain can be like a table in a restaurant with one short foot extension. Hard to stuff enough napkins under the wheel.
Skid gear, on the other hand, tend to sit on the high points, when there are enough of them.
Give me wheels to taxi around the airport.