My idea is neither JJ3 nor 1.25.
It's Guns of Jazz Jackrabbit.
Here is what it could include:

MUST be 3D like jj3.
MUST have editor.
MUST have object editor (like jsd in jj2).
Must have dialogs with interaction.
Upper left: Face of rabbit.
Upper right: Name of rabbit.
Center: What he says.
Below: What YOU say HIM.
Tasks and missions with stuff done flags.
Super bonus if you collect ALL coins in WHOLE EPISODE.
Bmp, Tga and Avi textures.
Transparency mask.
Background Layers.
Animated textures.
More animation libraries.
MP3 music reading besides mod plugs.
Single sided 3d objects (so you don't see inside the head).
A large inventory.
4D doors (like carrot shop in jj3).
Graphics like play station three.
Home cooked levels list.
Automatical targeting.
Perfect functionality on windows ME, XP, Vista.
Unr to JGM (jj3 to jjg maps) converter.
Sold in all 6 countries.
You control Eva and Devan.
24 bit tileset textures.
Devan steals your gun.
No silly terms (musting write brackets that not exist on your keyboard.
Tell your own ideas.