totologic (./16):
- no abstraction for the display, I like to experiment my own code and build my own exportation tools because I think it participates to the visual identity of a game.

I think you missunderstood NGDK's abstraction. There is no abstraction for the display aside from how you create sprites and how you move them and update their tileset etc. How to create palettes.
There are even Background and animation helpers, but I did not used those cause I just have two 512x200 background layers and I just did those with sprites. I haven't used the animation helpers cause that's pretty basic and I had to create animations with a fixed floating point cause the game have a slow down mechanic. (I used SGDK's fx16-fix32 )

I also cannot understand how the tools can participate in the identity of a game.