That's nuts. I was going to do Warp Man myself until I saw Ryona's Warp Woman!... Sorta had an idea he'd pick Megaman up, teleport to drop you above some spikes, and you'd have to navigate the right way in time-- something along those lines. Ya beat me to it! Anyway, I ended up creating TEMPO MAN. I guess the series never felt the need for a music-themed boss what with all the music references already (Rock, Roll, Blues, Bass, Treble) and the great music, period.
This is all I have done for now, but I plan to make a Megaman-sized sprite as well as some level tiles. He's just got some shades, spiky hair and some big headphones. Yeah, nothin' too exciting yet.
And yeah, I agree Warp Woman needs to fill up a bit more of that frame. It's great the way it is now, but I've seen your other excellent sprites and I'm quite sure it could be even better. (I think mine's too big actually...)