Here is the transmitter board I just layed out:
The challenge of this is that this board is really small. The mistake I made with the first board is I didn't choose an enclosure first. For this board I chose a small enclosure and create the mechanical outline of the board first. Then the challenge was to route everything. This board is only about 2.25 x 1.25 in! To make things worse it has a battery holder (which is mounted on the bottom) so that prevented me from putting any vias other than ground in that area.
As I mentioned I didn't choose a enclosure before designing the receiver board, so I had to find a bigger one and modify the board to fit it:
Just to get a perspective on the size of these things: