Sp, this is a thread on Piracy: A primer. How does Piracy work in your Universe? How do they attack ships and get away before they're nailed to the barn door by the Imperial Navy?
It is one thing to calculate how much money/revenue that the pirates can take if they successfully abscond with a hull they've captured. It is another thing to actively take a ship, get past the override codes, the fail-safes, etc - and get away.
So, give us the details
I have no Imperial Navy.
Well I am a bit loath to go into detail as this is an arena of mystery and discovery about 'how things work' IMTU.
But I can shoot for broad strokes.
The part time or mortgage skips try piracy the way you suggest it, overhauling a ship the hard way.
That could work, although I expect a more common occurrence is dump over pleasing cargo (maybe even loads or cash boxes on hand for the occasion), the pirate comes and scoops them up possibly with a high-G small boat, essentially a pirate tariff/protection racket.
For actually getting the target ship to cooperate quickly and give up the ship with codes intact, the pirate crew will have to have the reputation of absolute safety if you give up, and absolute death or worse if you don't.
But, that's the amateurs.
The professionals will operate on another level.
They will hijack, and not just pistols, but sophisticated crew takedown and control.
They will get crew onboard for intel and acting at the right time.
They will operate on intel, know your routes and weaknesses and strike at optimal times.
They will cause fuel leaks to spring as the ship heads to the jump limit or perhaps jump drive fuel pump sabotage, so when it's jump time, the ship can't jump.
They will slip into standard jump lanes with those false flag-IFF corsairs, to be able to pounce on prepped ships like the above, and slip away without showing true colors if the target becomes too hard.
They will otherwise do most of their boarding with much more expendable and fast small boats.
A unique feature of my pirate clans is that they are a long-term community, less opportunistic Caribbean pirates and more Black Sea Cossack Pirates. So, they are particularly interested in sustainability and practical matters.
One of the things they do is arrange for cargoes to be shipped that contain things like starship drives/weapons, high grade medical equipment/drugs, makers, etc.
They will then 'capture' the subtly cooperative ship, get the agreed-upon cargo for the arranged price, and pay in cash or illegal drugs/guns/biotech from the Cloud either right then or in some back channel way.
Chumps chase ships. Professionals have the ships come to them.