Sliding dovetail gaps - filler?

I am building a secretary-style desk. I used sliding dovetails for all of the drawer separators as well as the desk top. I guess I should have used a stopped-dado there instead because there are small gaps on each side (about

I am trying to keep seasonal wood movement in mind in attempting to solve this problem. Both sides and desktop are glued-up panels of cherry (3 pieces each). Theoretically, the seasonal movement experienced by the sides should be the same as the desktop.

SO.. should I fill the gaps with homemade cherry filler or should I make some decorative mouldings to cover them up? Any other ideas appreciated.

Thanks.

-Bob