Thoughts

So I did some more math and thinking about how exactly the game is going to play out. I think our best bet to keep gameplay flowing is to have transitioning from one phase into another at a specific time. Split evenly, that would mean that there would be a transition into a new look every 100 seconds (or 1 minute 40 seconds).

This way we can make the difficulty curve scale pretty well, too.
If 1-Bit lasts for 100 seconds and you have to collect 8 bits, that's 1 bit you have to collect every 12.5 seconds.
If 8 bit lasts for 100 seconds and you have to collect 16 bits, that's 1 bit you have to collect every 6.25 seconds.
If 16 bit lasts for 100 seconds and you have to collect 32 bits, that's 1 bit you have to collect every 3.125 seconds.

It also gives us some room for mistakes and the ability to really play with the "story" that gets told. We could put 10 bits into the 1 bit phase (or 8 bits and 1 bit cluster) so that the player could end out lagging behind in 8 bit or being ahead. In 8 bit, the bits might be easier to come by, but require a bit more jumping/enemy dodging in order to get them. In 16 bit we could have much more than 32 bits in there so that if players lagged behind they could catch up. I'm thinking that we can safely put in a LOT of bits into the 16 bit phase, as we want the end result to be a game that you play to try and beat your previous score in 5 minutes. We don't want it to be impossible to finish. So the sense of being rushed becomes more and more prominent the further through the game you get, and you face more and more enemies as you try to collect more and more bits.

I was also considering how we can make the transitions work, and I think with this layout we can make it happen really quite easily. At 100 seconds into the game, the background, platforms and enemies transition into 8 bit. At 200 seconds into the game, the background, platforms and enemies transition into 16 bit. At 300 seconds into the game, the game ends. This way we can create a play area that takes a little over 5 minutes to cross (based on the players movement speed) and simply load in different textures every time the timer hits a certain point.

The Player character would develop separate from the timer however, and would load in new textures based upon their bit count (so at 8 bits in the 1 bit phase, the character loads in a new sprite - whether or not the game has reached the 8 bit phase). If we wanted to we could easily reward the player for pulling this off with extra points (I was even thinking a little text popup saying "Ahead of its Time!" or the like, since this is a game based on games).

Just getting my thoughts out there.