I also cannot understand how the tools can participate in the identity of a game.
What tools do you use to create your art and animation ?
You will have different results if you use Paint, Photoshop, 3ds max, Animate, Spine... And because none of them export directly optimized file assets for the Neo, we must write the relevant tools.
For example, if we take Street Fighter and Mortal Kombat, it is not hard to imagine how different were the tools and methods used to create the characters.
Looks like I misunderstood you, cause it seemed to me that you were writing a pixel editor.
I believe that convertion tools can only give limitations and not advancements.
I hope we can standarize (even across SDKs) the way we add graphics and sounds for our games in the roms.
Kannagi had created graphics tools for this and at least the way those tools are used with NGDK is in my opinion the easiest possible way.
Back then games were made by dev teams, in the homebrew scenes two people working on the same project is a luxury.
We have better tools but we lack in man power.
I had a discussion with a MegaDrive dev who was active in the days of the console and he told me that they had SDKs too in the form of routines in assembly. For example the code for animation, collisions, transitions etc was reused in many games, they also had experts working full time on the in house tools.
The knowledge required to do what they did is very wide and without the technical and economical support they had it is almost impossible to be done from only one person. Also if we consider the advancements we have today in game design, the required knowledge is even wider.