I think there should be formations, with the afformentioned facing options, and with a subset of attack styles available for each formation.
For instance, you might have options like line formation, box formation, and echelon formation (Short-range Frigates in front, Cruisers and Long Range Frigates behind them, Long range Cruisers and Capital ships in the back).
Then from the line formation your attack style options might be Encircle, Flank left, Flank Right, and Hold Center. Your echelon attack styles might be Hold, Slide Left, Slide Right, and Slow Retreat (this would require the ability to move backwards at least very slowly, so that would need to be changed too). Then whenever your formation encounters an enemy they would immediately implement the current attack style.
So lets say to otherwise equal fleets run into each other. Fleet A is in line with the attack style set to Flank Left. Fleet B is in echelon and set to Hold. Fleet A would start moving slowly to the left as a whole, and the ships starting on the left would begin moving forward. This would bring lots of firepower to bear on the right side of Fleet B, quickly reducing that side of the fleet to a shambles, and without further intervention Fleet A would eventually win, but not by much. However, if Fleet B had been in, or was quickly changed to, Slide right, then they would bring more focused power to bear on the advancing left side of Fleet A, and would win by a considerable margin. Similarly, if A was flanking right, and B was sliding right, then A would flank the heck out of B, and be able to destroy B even faster. Of course if A did a slow retreat then any attempt to flank or encircle would be death for the line formation, who should instead hold their line.
