Ever since this thread was bumped, I'd like to correct myself on earlier posts:
Ends up that, with metrics(fps); I was able to see that Blockland runs on 300+ fps on Gamemode_zombie No Mercy Subway without shaders and ~34.5 fps with minimum shaders.
For some reason, however, the laptop appears to be struggling to render that. No idea why, no other lag appears, runs smoothily.