I suppose it depends a lot on which targets you favor. Personally, I tend to prefer galleon types over sloop types, and sloop types over frigates; at this time, EITC Ogres are my favorite target.
Since the weakness of the galleon types is in the bow, I spend a lot of time as the chasee rather than the chaser. I depend quite a bit on not just seeing "established contacts" but also getting position, orientation, and bearing information from watching my compass. I depend on instrument sailing mostly for finding dead spots, and getting myself in position in high-traffic areas. I used to do almost everything with broadsides, now I soften all my serious targets with Thunderbolt and Flame Brand from a distance.
So, since I hit level 12 Cannon (about 600 points from 14 now), I've sunk almost all of my intentionally sunk frigate types either entirely from outside their cannon range, or by taking out their sail power and picking by ingress route carefully.
My favorites strategies aren't that much different for any type though, just for frigate types I apply the idea to the aft instead of the bow. Oddly, the bases for my attack methods originated from playing the tabletop game Star Fleet Battles (yes, I mean dice, hex maps, cardboard counters, and energy allocation forms).
With galleon types and sloop types, I try to approach from the front but inside the ~45-degree cone of cannon blind spot that extends out from the bow (sloops can waggle their broadsides to bear much faster than galleons though, so you may want to stay inside a 30-degree cone as you get closer); unless they're pretty close, a ship that has you targeted will tend to point straight toward you though (meaning galleons and sloops are happy to show you the weak parts of their hulls, whereas a frigate would be showing the well-armored business end).
Knowing your turning radius for the ship you're in, and keeping inside that cannon dead spot, I turn out in front of the vessel. As long as you make keep your wits about where you are, you can sail out in an empty direction, dropping sail and turning to broadside as able (once you get a feel for distance you will be able to reliably put 2 broadsides across their bow before you have to raise sail and move again, of if you're sure a 3rd will finish it then you can squeeze in a 3rd...made easier with some Taskmaster points). So, I try to stay in what I would call their Front Arc (FA).
Knowing the limits of the cannon dead spot in front of the frigate, you can also get a feel for timing when you raise your sail from a broadside cycle and get yourself into a turn (you have you jog your turn wider, by turning back in the opposite direction very briefly every so often) that keeps you and them perpetually turning with you in their blind spot...then you just spin kill them as your broadsides recharge. This is more useful in crowded places, where you can't keep running out in front of an enemy forever; however, you have to be very careful about the pace of your turn once you start this with powerful ships, because if you fall back a hair into their firing arc they'll hit you extremely hard due to the close proximity (in my light frigate days, I had some type of skeleton ship, that spawned right on top of me, one-hit me with Thunderbolt).
So, for frigate types, I try to take the same oblique run-in approach, but to the aft of the vessel; however, since I got Thunderbolt unlocked I'm not as picky about which end, just preferring it be moving either directly toward or away from me. At this point I'm pretty comfortable with "de-sailing" some pretty big ships before they get in cannon range, but until your comfort level is high it is better to move back a little farther when dealing with frigates.
Before I unlocked Thunderbolt though, I made my oblique run inside the 45-degree cone projecting from the aft of a frigate; however, instead of turning to sail directly away from the aft of the frigate, I'd extend the run-in a little bit (trying to time two broadsides on the aft before you have to turn to stay out of their cannons on the other side). You will get tagged a few times before you get the timing of making the turn and you'll need at least 1 point of Come About and some Tacking doesn't hurt, but the idea is to make a fast turn away from the frigate and hopefully get one broadside from your ship's other side (so, when all goes perfectly, 3 unreturned broadsides to the weakest part of the frigate).
Also, unlike spinning a galleon, you're spinning a frigate from the aft, and it's a bit easier with a little more distance and your ship should be turning in the opposite direction of the frigate with Come About. Optimally, after you Come About you want to drop sail right behind the ship and put your ship in reverse holding it in the Rear Arc (RA) cannon dead spot of the frigate type; just like spinning a ship from in from of it, you'll need to get the hang of jogging your turn a little wider to stay in the dead spot. This might take a little getting used to since you're now trying to get used to pointing the aft end of your own vessel wider, in the direction of the turn.
EDIT: I thought I might try my hand at illustrating what I was talking about, as that might make it easier to visualize.
