That's a clever way to use the coutndown as timer but also as obstacle!
The music is getting too much repetitive.
Maybe the 3 times clock could be used inside one level to force the player to complete it in a short time. Or use it as "stars", people may want to finish all levels before one tick.
The level with the gear propulsing you in a plateform is a bit hard, it may be interesting to have a second option more easier but longer, the first one would be use for speedrunning.
Keep going!