At this point, the only thing of FC I would suggest using in SFB is the ship cards, including fleet scale. (And, I have a nice article in the last Captain's Log that explains how to.

) I would hesitate on the rest, as the unintended consequences could be pretty brutal.
Three examples that could be done that would have devastating repercussions to the rest of the SFB game engine:
- All power is reserve. You only have to "pre-allocate" movement, multi-turn arming weapons, and continuation power (e.g. tractors) in Energy Allocation. Everything else is reserve.
- Decelerate at any point in the turn (for energy, of course).
- Allow mid-turn speed changes with "all power is reserve" on a one-to-one basis. (None of this sometimes two-to-one silliness.)
Doing one of those three would be a pretty impressive change. Doing all three (which is still only taking a very small part of how FC works) and putting it into SFB would completely change how the game is played.
Seriously, I recommend just playing SFB as SFB.
EDIT:
Eh, I guess you could use the FC damage allocation. However, several things in SFB are designed around how the SFB DAC works, so, again, you are staring down those unintended consequences again.