After 63 levels, finally acquired a Hyperion! Had to save-scum a deserter bounty fleet to board it. Each attempt, I parked outside of Aztlan system, then gate in and travel about two weeks for Toci, where the bounty fleet sat. If random events vary in that time frame or less, then ships eligible for boarding change too. (I noticed that after my previous Onslaught capture attempt, which I finally boarded thanks to Special Ops perk.)
First attempt, I had a chance to board Aurora. Nice, but I really want that Hyperion!
Second attempt, chance to board Falcon. Ugh! No thanks!
Third attempt, nothing, just salvage.
Forth attempt, Hyperion offered! Time to act like Gollum!
I have yet to configure it since I do not have the weapons available deep in enemy territory and since I brought three Atlas with me, I will make it worth their while by grinding Hegemony detachments until they fill up with loot. Maybe I will board a XIV ship while I am at it.
One more thing: Special Ops perk is very, very nice! No need to bring 500 or so marines in a liner in case a capital gets offered for boarding.