I didn't do a full mod because I have to go now, but I will when I get back home. I probably won't have much to say anyway.
For instance, you should force a custom sliderborder.
It looks way better. Seriously.
I suggest using either this:
SliderBorder : 60,60,60
SliderBorder : 210,210,210
Any of those looks better than the default one. Remember to add the code under [Colours] on each .osu file!
Oh, and something I saw in the Collab:
02:32:817 (1) - Place the end of that slider in a way that it isn't overlapping the slider track. Not only does that look bad, but it's also a point in the upcoming new rules that states that you can't do that. For real.
Well, good luck and sorry if you have to pop for this!