4

I think it would be interesting if the player was able to specify the width and height of the playing field in kblocks. So for instance they could make the level very narrow, which means that it would take fewer blocks across to get a line (but also means there is less room to maneuver). Wider playing fields would require more blocks across to get a line. Shorter playing fields would mean you reach the top more quickly, while taller playing fields means you reach the top more slowly. This allows people to alter their play experience however they want. A narrow and tall field would be good practice for beginners, while a wide and short field would be for experts.

If Hans' Co-op mode idea is implemented, a wider playing field would probably be desirable for co-op mode, but someone people may like the franticness of having two people trying to work simultaneously on an ultra-narrow playing field.