This is something that jumped to mind earlier and simply put: When the recorder screen is up and recording from the FM tuner, the available options seem a bit 'lacking'. Notably: To change stations you always have to back out, go to the fm radio page, retune, back out, back to the recorder. Feels a bit counter-intuitive. Even if you are not readily recording anything, but are planning to, it's more steps than necessary in my opinion.
At the very least, maybe add an option below the gain and volume sliders to run through either scan mode frequencies or the presets in the same fashion as the volume/gain sliders. Or you could probably get away with an extra option on the long-select menu.
If I can ever wrap my head around it, I -may- attempt a patch. Who knows.
EDIT: There's also the little obviously missing function of being able to press the record button while in FM radio mode and going right to the recording screen and save a few steps. At the very least on my e250 with the latest SVN build as of this morning (Mar 22, 2009), this seems to be missing. The REC button does nothing while on the FM screen either a quick press or a long press. I don't even think it does anything in the recording mode either.