Thanks for the compliment!
To answer your questions…
the intro screen looked really cluttered with two signs on the screen at one time and it was a little confusing for the player to understand what to do. Obviously, you are not supposed to squash the passenger so if you picked them up properly the first time, you would never see the second sign!
I guess it could but they you would have to press multiple directional keys simultaneously. Maybe a mod for Version 2?
Yes, this is a known bug and will definitely be addressed in Version 2.
One of the things I need to do for Version 2 in addition to the previous is free up some PROGMEM space for some additional levels.
Right, at the point where the game is sitting idle (on the splash screen) and a user would be able to flash the device there should be very little local variables allocated or stack / heap use due to looping. Of course its just my inclination but I have been wrong before.
Is there any way to really measure or calculate the dynamically allocated memory use the game?