Its not a pulsar buff if you increasing their cost. Right now the difference between Shadow and Vaul is 71 point which is huge. For 71 point you loosing two cannons with 3 dps each, but gaining 3 pulsars which is harder to use and have 5.25 AP dps each. Also Aurora light cruiser is only 21 point cheaper then Shadow. Now you can take 4 vauls or 7 (!) shadows.
tl:dr There are no point to use anything in Corsair fleet now besides Shadow spam.
So you may either increase Shadow cost (which I would prefer) or decrease cost of ships with pulsars.