[Stan.]

This looks really cool, but I'd like to offer some suggestions you may not like to hear.

I've been making games for quite a while now myself, and I can practically guarantee you that if you continue to be as ambitious as you are now, you will not ever finish this game. You will lose interest or have no more time to work on this game inbetween now and three years into the future. And even if you don't, your fellow game makers almost certainly will. I've seen dozens of great projects die this way, including a few of my own. And I've seen almost none of these ambitious projects completed. (Unless the people who worked on them received money for doing so, that is.)
Because I'd really like to play this game, I'd like to suggest: make the game smaller than you're currently planning. You can always expand the game after it's finished if you still feel like doing so.

Another suggestion I have is to, well... not blow up Oddworld. I suggest making a story on a smaller scale. Create something that doesn't (drastically) change the current Oddworld cannon. Fans might even accept it as a semi-cannon part of the Oddwolrd saga if you keep it small, believable and if it doesn't change Oddworld as we know it. What I'm trying to say is: people probably wouldn't even take it from Lorne Lanning himself if he destroyed Oddworld or (for example) killed off the Mudokons. And they certainly won't accept it from you.
Of course, the whole game could be a 'what if' story. But even then, I think not drastically changing Oddworld nor trying to continue the story after Munch's Oddysee is best. Make Fred's tale a side-story.

This is just my humble opinion, of course, but I do believe this could make your game better. Also, if you do these things, and possibly even if you don't, I'd be willing in helping create some sprites. I can only do 2d art though, so if you were moving to 3d-rendered sprites I cannot help out. I can help in designing game mechanics too. I'll post some examples of other things I've done later and let you decide if you'd like my help.

Good luck with your game!