HaxePunk uses OpenFL which means you can compile to just about every device. A lot of the rendering code has been optimized so if you use HaxePunk’s graphic classes you are pretty much ready to deploy on any target.
A generic Entity system that only uses what you “attach” to it. If you need collision masks they are available but if an entity doesn’t need to collide with anything then simply don’t add a mask. Same goes for graphics.
HaxePunk has added several collision masks beyond what FlashPunk had including a grid with slope values, circles, and polygons. This is in addition to FlashPunk’s tile grid and hitbox.
Tweens are available just like they are in FlashPunk. If you need to interpolate values for sounds, movement, etc… it’s probably already available as a tween. There is also a VarTween that lets you interpolate any value you want.