It looks to me like theres only individual level speedruns. Is it possible for me to do the whole singleplayer speedrun?

I second this request, it would be a fun mode to run.

Edit: we may not hear from the moderator as they have been offline for 1 year.

Edit2: Full game categories have been added.

LET'S BREAK SOME REKKIES, BOIIIIIIIS!!!!!!!!!!!!!!!!!!!!!

does the bonus level (level 25) in the campaign count as a level, or should I end the speedrun timer at level 24?

I think that the definitive run right now is the segmented run by Major_Shade, this includes level 25.

But this was run in an earlier version, I think that 0.8.6 has an extra level or something? I would have to play it through again to check.