We are just adding the final stage of the new UI system to Skyline. So far there is a cool new real time, html script driven UI editor which can make standard developer tools for your project( windows,sliders,checkboxes etc) and then be used to make full interactive game screens. We are currently hooking this up to Skylines main scene editor so it can be include with the scene. We have also planned many lua commands to control the new UI system and many of these will enable dynamic content, by using these and lua to code your collisions you would be able to use the UI system for a 2D sprite game. Alternatively it has become popular to use the 3D scene and a fixed camera for developing a 2D style of game (2.5D).
If we get a lot of call for more advanced 2D features we will look deeper into this area of development
BTW: We have a running poc of a node based script editing environment which we hope to get to you later this year