I'm finding patrolling in a strong hold to be pretty good, you get great bounties on power USS's particularly the threat 5 ones, some fun fights. If you pick up the black boxes and wreckage, that soon all adds up.
Interdicting any enemy in sight who is also wanted, those get good merit payouts, and also the convoys give you a decent balance just for very quickly blipping though all the ships in the convoy with the next target select, and then killing any enemy power ships that also instance.
Honestly I find it a fun and immersive activity, playing the game rather than grinding. I'm not sure how much fun those threat 5 enemies would be, if I'd not had any PvP training though. They seem to have upped the anti somewhat on those, way harder than pirates in the asteroids, I've found anyhow.
... On my todo list is tracking down the powers most wanted from the stations local galnet news, I was surprised to find that they can be quite a distance off, which means it is not so nice to do in an FDL which is also kind of cool. [That said, I've also just learned that there is a way to temporarily boost the FDL's jump range from the right hand console, and have not tried with that yet.]
My phantom is now also proving to be quite successful for combat, and is a lot of fun to fly with the extra range and better super cruise handling.