Walt It would definitely be convenient (moreso for people who use attack angles a lot), but it wouldn't really let you do any of the things you could do with enemy-relative facing and grid-relative movement.
Examples would be something like disengaging from an enemy before you hit the zone, but keeping your spinal weapons focused on them so you don't get disadvantaged by retreating. Or breaking out of surrounds from a swarm while keeping spinal weapons focused.
Ideally you would be able to do all that while focusing weapons on a specific part of an enemy ships, instead of only center +/- a degree offset. But if that's not feasible I understand
It's only really needed for spinal weapons though. Turreted weapons can hit their target if you only use move commands and just approximate the correct facing.