There we go, last bit of drum kit upgrading for the time being: I got a proper drum mat! With my old setup the kick drum pedal was hard against the cymbal stand that's poking down there at the right, and the hi-hat stand would end up getting pushed back into the left of the drum frame. With the new setup if I really put the boot in, the kick drum pedal would end up migrating its way back, and the hi-hat stand was in an awkward position. I've added velcro to both now, and they are absolutely not moving. Plus a bonus, the kick drum pedal makes far less audible sound now that it's not booming directly against the floorboards.