Well obviously our experiences differ.
I have found that MORE pirates makes it easier, that last several battles I participated we had several high level pirates... mostly all over level 30, including a few level 40's. The frigates go down in a few seconds with 4-5 people with high level cannons on each side.
It depends on how the one at the helm approachs the battle, and who you crew...
And yes, Take Cover DOES work.
