I chose not to include -5V as there are only a handful of older dedicated boards that need it. The change in power supply and extra wiring simply can't be justified for the three people who may want to use a board like this.
This product is primarily aimed at the end user who will simply plug it in and away you go!!! However I have made sure it is as "collector friendly" as possible as well within the constraints of the budget. To add -5V would have cost an extra $25 per machine and I felt the remote controlled undercab lighting (at the same cost) would be of greater benefit to the maximun number of users.