My experience so far with the Fokker is that for a successful flight, you need to get it off the ground as quickly as possible. My lower wingtips are scratched up pretty good as a result of a few embarrassing ground loops. The good news is that this little plane can actually hold up to some really solid abuse.
My suspension solution here has not been tested out yet but I wanted to make the files available early. I took a shot at redesigning the gear wing to allow for at least some suspension to smooth out the little bumps. Aside from a very tiny notching out of the rear gear legs, this is a direct replacement to what you already have.
The axle is now a 4mm piano wire supported at the center of the gear wing and allowed to ride up and down at the wheel locations. The gear wing is given some rigidity by the addition of two 2mm carbon rods that will be CA glued in place. See Pic:

Until this model is tested I won't include it in the main model files, but if you wish to receive it I set it up as a free download. Make sure to use the discount coupon indicated for free.
https://www.redbaronrc.com/product-page/fokker-dr1-suspension-modification