My notes:
1) That's great
Are they working ?
2) Your board seem to use too much vias. Normally it should be possible to design a NROM board with no more then 3 vias, I can see dozens on your board.
3) Your traces seems very thin. This is not necessary wrong for signal traces (only the power track actually need to be large), however, the only point of thin traces is to be able to fill a lot of them in a narrow area. If there is no such extreme demands from the physical layout of the board, you're free to use bigger tracks than the minimum available, it never hurts. Personally I used 20mil tracks on my NES board design for signal, and 50mil for supply lines. This is way more than the minimum, but again, it doesn't hurt. If in a particular place I have to make them samller for them to fit, then I will, but only in that particular place. For example, if you need to fit 2 traces between 2 IC pins, you can reduce them to 10 mil just for that part.