I've been running a campaign lately where one side made use of boarding combat, and it struck me that five minutes per increment is a long time, possibly too long.
The basic situation was a jump point assault, where the defenders had a combination of mobile ships and also weapons platforms on the jump point. The attackers jumped in and, after considerably battering down the defenses, started boarding on the weapons platforms and some disabled ships.
It turned out that five minutes is an extremely long time in this scenario. Even with most of their weapons disabled and holes in their armor for instant boarding, the weapons platforms were able to inflict considerable damage, mostly emptying their magazines, in that time. Even though the attackers had such superiority in numbers that they were able to take every ship on the first increment of boarding combat.
I do think that boarding shouldn't instantly remove a ship from the fight, but I can't help but think five minutes per increment is too long, especially without any mechanic that diminishes a ship's fighting ability while it's being boarded if the attackers have overwhelming force.