The other point to consider here is, unless one restricts ships to "one combat per turn" (and THAT would send FAR MORE people howling), it's a kinda useless mechanic. Oh, my pirate opponent managed to get away. No bother, I'll just kill him with the five moves I have remaining.
Unless one attacks on their last movement point, it just becomes a tedious "move sink" to deal with people who survive a battle. Not saying that it can't be looked at via DLC (which makes it optional) or some sort of expansion mechanic. But it needs to be given a long hard look before doing so.
1) What stops people from pressing the attack?
2) How will people react to not being able to continue hostilities if there is a limit to re-engaging?
3) What are the knockoff effects of P2 that might not be immediately apparent?
For point 3, consider that hit and run tactics are used quite often in the game right now. If some sort of "attack and end move" occurs, that goes out the window. If some sort of "attack, can still move, but can't attack anymore", not only will the immersionists howl, but the folks concerned with "mopping up" large amounts of cheddar fleets (lots and lots of small opponents, unstacked, that are trivial to deal with but take lots of battles to finish) would start to grind their teeth in frustration. Especially if the opponent was smart enough not to engage in suicide tactics and kill themselves by running into your deathfleet.
In other words, this is not a simple on-off switch. There are lots of considerations at play. The first being "go big" (the current model) or "go small" (the Civ 4/5) model when it comes to the number of attacking units. "Escaping" units make more sense in the later. Less so in the former.
