Back to "Super smurf Rescue" i suppose Coleco's fan expect that the game would be as "planed" (i mean for instance graphically ). if an "homebrewer" made the game said "better than it would have been" , it won't be good, is that correct?
This is just my opinion, but I think the Smurf graphics/animation should remain the same (I just had a look at CV Smurfs Rescue on YouTube, and the sprite animation looks pretty good to me). Perhaps the jumping animation could be altered to match the way Smurfs generally jump around in the comic books (I believe you did this in Smurf Challenge). Aside from that, I think the background graphics could be spruced up a little bit, but not too much.
More importantly, I envision Super Smurf Rescue as an exploration game with branching paths: The player would need to explore different areas, and locate certain items (like a key to open the Smurfette's cage, or an apple to throw at Azrael's face, to open the way to Gargamel's lair). So it would be something like an extremely simplified Metroid-style game with some mild backtracking, and the items to collect would be scattered randomly throughout the game world, so no two consecutive game sessions would be the same. Areas to explore would include the forest, caves, inside tall trees (like in Opcode's Magical Tree, but inside the tree's trunk), ponds, prairies and mountain paths (like the promo screenshots), etc.
The nice thing here is that very little is known about that particular waffer super game. So while it could look a lot like the known screenshots, there would still be a lot of room to exercice our homebrewing creativity, and make a really fun game that takes Smurf Rescue to a higher level, which I think is really the point of making a super game in the first place.