Yeah, if you are able to reach high crit rates (ideally 100%) then I believe the crit build (the first one I posted) is slightly better (replace with the weapon-appropriate S5, of course) thanks to not having any build-up time. if you're wanting a look at S-Grades for hero and phantom, I can offer some recommendations, though.
Hero has a skill on it's tree called Precision Attack Critical that gives hero an extra 150% critical rate when hitting an enemy's weakpoint. This makes the idea of running crit builds on hero very appealing, but afaik this is also hero's only source of crit rate, so you should take that into consideration before spending money on SGAs for it. Notably, however, this extremely high crit rate allows hero to use S4: Precise Balance (whether or not it is better than escalating pursuit I have not checked, but this felt worth a mention regardless).
As for Phantom, I don't remember any particular SGAs of note. S4: Steadfast Will appears to be a rather popular choice for rifle players, but how much good this will do you depends on how much you rely on normal attacks. IIRC, phantom struggles to get high crit rates, so non-crit SGAs are more worthwhile.
Finally, with the release of solo Sodam, a few SGAs have gotten cheaper or easier to obtain, notably S1: Aggressive Will 2, an unconditional 4% damage up. At least on my ship its nearly dirt cheap, and it's unconditional nature in addition to it's rather good potency makes it excellent for side-weapons or as filler.