Context: I'm trying to design a massive colony ship (as in, at least 3 billion tonnes unfueled), built by a hyper-advanced K2 civilization, that will be accelerated via laser pushers and will use a black hole drive to decelerate. Since black holes have a similar matter-to-energy rate as antimatter, I figured that I could figure out how much speed a ship of a given size could eventually burn off by treating the black hole like an equal mass of antimatter. (I used the relativistic antimatter rocket equation I found on wikipedia for this). However, the quirk of black hole evaporation means that simply scaling up a ship with the same mass-to-black-hole ratio will make it decelerate much slower.
I came up with a workaround to this problem, which is to make a bigger ship use many small black holes rather than a big one. I won't get into the weeds of how the ship would harness multiple black holes at once (maybe in another question) but basically, if I'm not wrong, I could make a huge ship exert as much or as little thrust as I want by changing the number of black holes as long as they add up to the required mass.
So, the full question. Let's assume this black hole drive has an Isp of, say, 0.69c (which is what the wikipedia article suggests as an example value - I don't know how accurate it is). Let's also assume the drive itself is made of handwavium and will convert the black hole's energy to thrust at the same efficiency no matter how much power the black hole is putting out, and will never melt or be destroyed. Given this, what is the smallest mass of ship for which the g-forces of converting the black hole's final explosion into thrust would not kill a human crew?
Anything that can dampen g-force, such as pusher plate, can be used as well. So I suppose it would be useful to imagine the ship as a huge Orion drive, big enough to use a black hole bomb.
I need to know this because the "usable black holes per kilogram of ship" effectively puts a limit on how quickly any ship could decelerate. Now, obviously a way to deal with this would be to jettison black holes before they explode, but that would complicate the math and I'm not sure if it would actually give more performance for ships that are big enough to withstand the explosion force.