I have noticed that it gets complained about a lot when someone is up against tyranids or spacemarines and that is that that no one thinks it's balanced that their fleet can just be one hit KO'd when they have few ways of retaliating other than stay at a distance which is rarely an option for anyone who aren't eldar. the quickfix solution the devs have is to just make boarding capable vessels be expensive as heck. but this seems to create other issues for these boarding heavy factions.

my suggestion is that boarding be changed so that it doesn't act like a button you click to have the crew of a ship vanish from reality in a millisecond, but rather make it so that when a vessel is boarded it starts loosing it's crew over time proportionally to the troop damage dealt. this gives other fleets the opportunity to retaliate before their ships are de-crewed and it just generally makes more sense for battles inside the ships to take time from a realism perspective.

wel wouldnt that insetevice hit and run tactics? let them board an then use ability to fly away until the enemy ships crew is dead?

it is already sorta the case. i'm just proposing it be nerfed so the troops lost during boarding aren't lost instantly. so the "hit and run" isn't just "hit". the number of troops lost stays the same.

Yes I have also proposed this, make boarding a Damage Over Time effect which can be mitigated with additional boardings from your own other ships

This is a good suggestion, +1
It doesnt change the power of boarding but its a slight balance overall.

Yes! This is another thing I agree with on boarding. If not for balance, then simply for the effect. Ships should't 'hulk' in 1 second. I want each race to have different engagement times, as well as different troop damages/crit %. Things like tyranids just move utterly quickly and swarm the bulkheads of the enemy ships. They should be fast (but not instant) at hulking ships. Tau should be slow. SM should be....slow-ish, but they have a higher crit chance so that would make sense. In fact haha, SM would be cool because they send over such a small amount of elite troops and they could go from bulkhead to bulkhead, securing positions, moving forward, setting up defensive barriers...it would be neat to have SM on your ship just slowly taking out your troop capacity over the course of a full 60 seconds or something. Tyranids should drop you in about 10 seconds (from 0-100% troop damage). Orks about the same or just a tiny bit longer. and so on and so forth.

What I would like to see with Tyranids is that we reduce their assault range. Maybe eliminate the boarding craft all together, and half the distance you can board with tyranids. I even suggested at one point that tyranids only be allowed to board if they are in contact with the enemy ship. Now that would be cool AND thematic. Only problem is that we have the change the 'rush' ability for nids. It's just way too much of a burst of speed. Make it organic, make it accelerate, make it slower but allowed to maneuver well and over a longer period of time. Make them feel like they are 'hunting' and closing in on the kill.

I'm getting off tangent.

But yes to the OP suggestion.

I was actually thinking about this as well, so +1 from me. Aside from any balance implications, it would feel more organic that the ship is being slowly taken over from within as your troops attempt to fight off the invaders before the last one of them is killed off... rather than the tens of thousands of personnel that the vessels are supposed to house vanish in the blink of an eye. In return, though, boarding-heavy factions may need buffs in other areas if this puts them behind, idk.