Me, I'd start by erasing ALL the fills except those at structure boundaries. Then, and only then would I start pasting fills back in whenever the thing screams out for them. Not before. You've also got to get into 'pickups' rather than fills at anything other than major structure boundaries... The tiniest snare drum ghost or mini-fill is all you need, many times.
An arranger 'trick' you can do sometime, if you feel up to it, is record as MIDI files ALL the fills from as many related styles as you can. Then, in your DAW sequencer, you can import these at will, and give yourself a HUGE boost in choice of fills for any point in the music.
Another trick is to take a look at JUST the drum track in any well liked SMF's... There are some pretty good Beatles SMF's out there, if you look, and other things in that vein. Take a look at them in a sequencer, and cut and save your favorite fills and especially 'pickups', those not really fills, just slight punctuation, that drummers do to acknowledge structure boundaries without getting all up in your grill...
Often times, just copying and pasting the snare and hihat parts is all you need.
The EZ Drummer's drum SOUNDS were a huge improvement over the PSR. But the drum TRACK still needs work to be more drummer-like, IMO.
Something else to investigate in your sequencer is to look at drum hits (hihats, snares especially, kicks, whatever) and make sure the arranger derived SMF doesn't have all the backbeats, or just about ANY consecutive hits at EXACTLY the same velocity level. Kits like EZ Drummer and BFD have many, many samples per drum velocity, so there is no excuse for two hits to EVER sound the same. There's two ways to go about this. First, I think EZ drummer has a mode (probably called 'alternating' or something like that) where, even if you DO hit it with something that doesn't vary, it'll play two adjacent samples alternatively, or just go into your DAW and hand massage it...
Hope these tips help...
[This message has been edited by Diki (edited 05-06-2009).]