I made some progress on the layout for Dexter rev3. I added a small 74LS244 IC to control whether VSYNC and CSYNC from the LM1881 make it to the 24-pin connector on the bottom of the board. This is so that Star Rider can receive these signals but LD-V1000/PR-7820 games will not.
I also tried to pack in the resistors to reduce the board size. Once I add all of the new components that I want, I will probably start routing. I also am seriously considering reducing the IC size of the MAX222 and LED driver ICs in the interest of shrinking the board size some more.