A fairly strange request to be sure, but I think it could be informative to have a tickbox to disable the interpolation of the models (temperature, wind fields etc.) - similar to how there is the "Smooth Satellite Animation" button for enabling/disabling it.
Especially for the high resolutions now, having no interpolation would show how fine the grid boxes really are, and could inform users a bit on the effects of the interpolation (assuming it's non-linear right now?).
I think me requesting this feature stems from the desire to become more familiar with how the original data looks like on the grid.
Also, for the really fine ones like AROME 1.3km, the map zoom could definitely be upgraded so that it does not switch to the OpenStreetMap just as quickly/early as it does now.