I guess this calls for the master...
AbilityFrigateAssimilation -- Main takeover ability that most ships have, does not work on Elites
AbilityBorgTractorBeam -- Elite on beam ability that can take over Elites
AbilityBorgStarBaseAssimilation -- Unicomplex version of the main ability that can target Elites as well
AbilityBorgDroneMissile -- Strike craft variant that turns Borg fighters into cruise missiles, upgrades to call the main ability effects
BuffAssimilation is the big kahuna. It works off the total duration, minus the application of BuffAssimilationSuccess, currently leveling for a 2/3/4 second interval. During this time, BuffAssimilationSuccess is active, and triggers on the ship taking damage. Altering the span of time between application of BuffAssimilationSuccess and the completion of the file will change the ease of conversion for AbilityFrigateAssimilation, AbilityStarBaseAssimilation and AbilityBorgDroneMissile.
AbilityBorgTractorBeam is significantly more complex.
BuffBorgTractorBeamSelf sets up the conditions for operation, either finish condition can be altered to change the reliability, either by altering how much damage the ship can take before the ability is disabled, or by changing it's duration.
BuffBorgTractorBeamTarget sets up the effects of operation, how fast shields are damaged, how much mitigation is reduced.
BuffBorgTractorBeamAssimilate is where the assimilation occurs, currently on an eight second delay after shield failure, canceling early should BuffBorgTractorBeamSelf terminate first. Increase the delay and you decrease the ease of assimilation.