Just an idea I got when i was selecting my away team. In the beginning, when selecting your away team, you start off with your run of the mill red shirts, then later are able to fill it out with your own Boffs as you acquire them. Why not do the same thing with Fleet Support? The chance system can still be in effect, such as having a much higher chance of calling out your Miranda then your Defiant. And to counter the whole 'filling slots with the best ships out there,' have it so that you can only have one slot for a T4 ship and up, and more for the lower tiers.