I think you linked to the wrong game. Your link points to a game called Hell Trap (which is still pretty fun).
Link to Slime LoveI think your game is great - it's really polished and the gameplay loop is pretty good. I meant to play just a few levels but found myself playing to level 15. Cool stuff!
If I had to have two main points of feedback it would be:
#1: It's too easy. I made it to level #15 with only one death. For these kinds of games I think the difficulty really needs to ramp up around level 4 or 5. I also found that the difficulty didn't match the map progression - for example level #14 was probably the easiest level out of the whole bunch. Level #15 feels like the first level that has had any real difficulty spike.
#2: It needs more stage gimmicks: Right now each level has been 'jump/avoid' the spikes. While that's fine with the mechanic you have, I was expecting around level 4 or 5 to throw something new into the mix. Just as I was going "ok I think I get the hang of this", you want to throw something new at the player. For example, level 5 could be where you start to introduce sticky walls you can travel along at different angles/upside down, or bouncy jelly, or falling spikes, or walls that you can only bounce off a certain number of times.
Nice work though.