Thanks, still trying, where is the end of the level? xD
It doesn't feel cluttered for me, but it's up to you! :)
As for the Android build, if you have controller support on desktop it works the same on Android. I'm not sure about iOS, but it should work as well.
And, I know not many people have controllers, so you can use the TouchScreenButton node. It's very powerful - but a bit different from the regular Button node.