The ColecoVision was extrordinarily short-lived. Most popular consoles continue with game support for at least 8-10 years, sometimes 15 years. If we predict this would have come out 1987, I would say any 8-bit , 16-bit or arcade game up to at least 1994-1995 would qualify. As you say, though, you may or may not want to go arcade accurate with some of the most advanced arcade games of that time.
As far as power, I'd estimate, technically possible: G.I. Joe SNES
Technically, not possible: G.I. Joe Arcade (here come the polygons)
OMNI can't enlarge sprites, so G.I Joe Arcade would be hard to pull off, unless we used tiles. The first G.I. Joe looks like a NES game to me, so it should be easy. Aliens arcade would be possible with compromises, like not so many sprites on screen. We can put some huge 64x64 sprites on screen if we want, but there is still a limit of how many you can put in the same scanline (16 sprites or about 320 pixels, whatever comes first). But that is all from a purely technical point-of-view. Aliens would require massive amounts of ROMs.
Ok then, how about Double Dragon the arcade game.
This one should be possible with no major compromise, and we could even fix the arcade sometimes terrible slowdowns.
These are some great games and would love to see all of them ported to the Omni, which leads me to a couple of questions. What happened to the CV port of Moon Cresta from Opcode? It would be awesome for us CV owners to get that before the Omni version of Terra Cresta. Also, I ask again as my previous comment was not responded to, the Omni isn't morphing into an arcade port only console, is it? I still want the Odyssey 2 game updates, Atari classics sequels and some original games too.
This year I am busy with DKA and PM DX for the CV. After that, we will see what happens. And no, OMNI isn't going to be an arcade port only console. Arcade ports are just providing the initial wave of games, until we have enough installed base to justify all the costs with the new Atari/Odyssey sequels. I am also exploring a 3rd venue for the platform, to accelerate adoption.
Careful there, Eduardo... Gotta keep in mind the rules of engagement when making contact with a gaming community, especially retrogaming:
1) The more you try to please everyone, the less likely you'll be to achieve that goal.
2) Give people an inch, they'll ask for a light year.
3) Getting people's hopes up about what a gaming system can do will eventually come back to haunt you, no matter how noble your intentions are.
With this said, my take on this is that you should position yourself in a solid manner. The ColecoVision's history is a good teacher in that respect: Coleco acquired licenses to a lot of little-known arcade games (in addition to some heavy-hitters like Donkey Kong and Donkey Kong Jr) and it really paid off towards the console's long-term reputation.
Faithful reproductions of arcade games on cartridges is a good angle, especially for collectors, but everyone has MAME installed on their home computer today. On the other hand, retrogamers have demonstrated again and again that they'll buy officially licensed retrogames as long as the price is right, even if they have access to MAME to play those same games. So it's a 50-50 gamble.
This is just my opinion, so take it with a grain of salt, but what I think you should do is look at the Atari 2600 library and see which games you could take and expand upon, to create something new yet familiar. The specs of the Omni seem perfect for that.
Some examples off the top of my head:
1) Keystone Kapers: Pursue Harry Hooligan not just across the Southwick Emporium (as in the original game) but through other city locations as well, and plug in Kaboom! as a mini-game.
2) Riddle of the Sphinx: A Zelda-style remake of this Imagic game would surely turn some heads.
3) If RPGs are in the cards, a full remake of Dragonstomper or Crypts of Chaos seems like a no-brainer.
4) Some shooters have interesting potential, such as Fantastic Voyage or Solaris.
You already seem to share this vision with some Odyssey-2 titles, but I think the Odyssey-2 has limited appeal in that respect. There's a greater wealth of potential remakes in the 2600 library, and there are also several ColecoVision titles that lend themselves easily to re-imagining and expansion.
Just my two cents.
1) Not promising anything, just gauging opinions.
3) Technical questions are answered from a purely technical POV. I am not saying we will see SNES grade content anytime soon, if ever. Big games need a lot of time and money to accomplish. That isn't our reality right now. Can OMNI do almost anything available on Genesis and SNES? Most of it, yes, in some cases better, in some cases with caveats.
I agree with your comments about the 2600 library, and in fact that is my main goal, to extrapolate the Atari era into technology that it never had access to because of the crash. Problem is, right now, with the hardware still under development and all the investment I still need to do, it is hard to justify the required thousand dollars per game investment to get multiple games done and waiting for the hardware launch. I must be careful on how I manage my money. Once the hardware is out, then things get easier. Then I can invest on a game basis and get them out in a timely fashion. I agree this is a unique opportunity.