ad controls: Glad you liked it. Actually, the original idea was for the jelly to autojump like every 2 seconds while player would be in control only of x-movement. Using mouse instead of keyboard seemed then more appropriate to allow for ... hmm, let's call it "continuous control". When I moved away from teleporting to directional movement in one early commit I set it up again in the acceleration style akin to gravity in Crane Construction. The plan was to iterate to much tighter control scheme but I found I actually liked this "big momentum" way.
ad physics model: I guess the acceleration model is what connects this game with my submissions for the previous gosu jams. While I used some bits of old code as a base they were then heavily modified to fit the new use. I think the biggest help from previous project was knowing which pitfalls to look for in this area. E.g. I already knew it is good idea to regularly round coords or at least speed to prevent floating point operations to break the collision detection code, at least when dealing with static walls at integer coords. I am also trying to use static variables as much as possible – that way it is easy to change one constant up and down and immediately affect all parts of code while tweaking the "feel" of physics model.
Yes, I am looking forward to polishing it more once the jam. One such planned thing is to have the jelly squeeze/swoosh/rebounce a bit at the end of jump sequence so that it actually gets true to it s name.