>Today PNG 24 is the only way to achieve transparency with a 24 bits palette, resulting in unnecessary huge files.
That's not necessarily true. If you only have completely-transparent and completely-opaque pixels color type 2 will work, and if your total unique colors (RGBA) number less than 256 you can still do plaetted.
That's not necessarily true. If you only have completely-transparent and completely-opaque pixels color type 2 will work, and if your total unique colors (RGBA) number less than 256 you can still do plaetted.