@Photocopier & Howard: Thanks for the help, guys!
GunApe == coolest new game character of the decade!
If it's not too much trouble, could you list the MMF extensions you are using? I have Game Maker, and I'm curious if Fusion is superior in this plug-ins department.
Pixel Prospector looks like a cool site, congrats, Mr Day! (though I do feel a little left out by havin' you on that
other forum behind our backs...

)
>I'm not gonna blow a whole lot of time on it, but I should get it to a good place before I move on, right?
Great philosophy - especially for games with such a small team!

Nothing seems a greater risk to the birth of a game than to be hopelessly mired in details that could be fixed
after all the important stuff is done - or never - just as long as they are at that minimum good place. Of course it helps when the very first workable version of things is as awesome as your stuff is - seriously, there's hardly anything you've put into it from day one that didn't already kick all kinds of butt!

As for what to put in next, it depends on your personality: Do you get bored if you work on the same task past the beginning 'hey, that'd be neat!' stage, always looking for a cool new challenge, or can you soldier on at the tasks that are the most important to next finish? I would label each new thing you think of to put in the game with the following three settings:
- Green. Anything put in the green category is something either so esoteric that only a developer would ever notice, or with which the game could actually run, play, and be released without it ever having been implemented (e.g. wanting a colour change to an enemy, or having a special text effect over credits, or making something swish when you run past it, etc.).
- Yellow. These are things that make a difference, but which do not keep the game from running. This category includes non-serious bugs such as an animation fluttering. If you can actually get from start to finish without a feature, then it's a Yellow category feature (e.g. no specific animation for being knocked back by enemies, or no sound effect for an action like jumping, or no intro story, etc.).
- Red. These are serious issues, like the kind that can kill game play dead. These are the missing sprites, fall-off-the-screen, 'what happened to my controls', 'where's the last level' type of issues.
Therefore, anything you label as a red category action would be the
first to be worked on,
even if something else were more fun. The only exception would be if the fun thing could be done in a day or less! If you are the type who has to have everything perfect before you can even
think of moving on (vs. someone who paints in the broad areas of colour and then comes back to details if they have time or inclination) then this may rankle you a bit.... (in case you can't tell, I'm speaking of myself here

and have to go against my natural obsessiveness and try really hard to finish big things before the little things, even though the fear of people seeing my stuff half complete is nearly crippling - how about you?)
I don't know if you want to use such a system, or have one of your own, but if you'll permit me, I'll take the liberty of labeling your 'To Do List' (including past items and a couple of my own...) in the following way:
1. Fix intro text - green
2. fix intro re-entry flame - green
3. Add SPIDERBOT to the game... - yellow
4. Add health and coolant pickups to the random dropable system - red
5. Create a crate and container system - yellow
6. Create a point/score/money/RPG/selective end of level upgrade system - yellow
7. Continue creating intro sequence and main menu - as well as a "how to play" and credits screen - yellow
8. Start making City Rooftops Level End-boss. (MUWHAHAHAHA) - red
9. More Cityrooftops art - including kites and shit in the backgrounds... - green
10. terrain variation - building height changes, that sort of thing - red
11. I might just have to make a version that's obviously UI in nature. - green
12. The player model - yellow
13. and movement in general. - red
14. Complete the visible In-game HUD - red
15. Intro - yellow
16. Main menu - red
17. decide if there will be any in-game collectibles and if finding all (including hidden ones) is necessary for 100% & 'good' ending - yellow
18. level two concept - red

19. task someone who can be both prolixy and pithy to craft the story text or a set-up novelette - green

20. name the levels (one suggestion for city rooftops: Ghost Colony) - yellow

You may wish to get a community consensus as to the category of each item, or make your own judgement, of course. (I've numbered the list so its items can be easily referrenced)
Congrats on your new house!
JD