Personally I'm in love with the ship and having just upgraded to the Sentinel from the sale I'm more than happy with this tanky beast.
I have yet to find a real analysis of the systems in game that look at how to optimize the Sentinel (my favorite ship too), but I will tell you what it appears is the case from my time on Hardpoint, and you can investigate further. I've been hoping peeps will do this since the Sentinel came out.
First off, the Sentinel was designed as a stealth bird. It has the radar absorbing armor (with less armor value than the others) and you want to use that stealth advantage. So really when you're flying in stealth mode, I think you want a small, low signature primary reactor, and you want to outfit for low power. That means you want ballistics. In stealth you want to fly with the shields and the secondary reactor off, and use your engines and maneuvering thrusters sparingly. You're positioning tactically, but not for a dogfight. You want to be able to send missiles from nowhere, and disappear the moment after you launch. Plan to drift into battle silently, launch and drift away uncoupled.
Secondly, you have to practice trigger control and go ballistic, and in the event a dogfighter finds you, you want that big chin mount gimbaled so you can hit. The Revenant seems the way to go. Forget the cannon--it is too slow to target and can't hit dogfighters which means you have no defense. I would likewise suggest 6 Scorpions, so that when you need the guns you have plenty of push and almost no energy drain. The Scorpions are almost 20% faster to target than the BVRS so you will hit more often. They have much larger magazine that fires for far longer than the BVRS. They do more damage and have only slightly less range. Because they are significantly faster to target they will form a tighter fire group to the Revenant, and that gimbal will lead the fixed ballistics to their target. Put your nose where the gimbal points and your fixed mounts will find their target. Use the gimbal to guide the fixed mounts.
This is all theory, but it is sound given the stats on Hardpoint are still correct.
Web application for planning and comparing loadouts of Star Citizen ships with detailed component breakdown and summary statistics.
hardpoint.io
Things needing real validation include things like the ability of a single, low output S2 reactor like the Daybreak, to power the whole ship in stealth mode, and whether that sole reactor is enough given ballistics and no shields up. It's a big question and it seems no one wants to do a real empiricle study until CIG casts stats in cement, but I think you can check and see if using a single small reactor really gives you enhanced stealth, and that should be a goal, IMHO.
BTW, shields are a more personal choice--do you want to be able to take a huge beating all at once (like flying against the Vanduul with plasma weapons) or do you want to be able to circle and recharge your shields ASAP? You can choose to do both. You can have a heavier shield up front where your first encounter will be and a fast recharging shield where your hits will come when you retreat and circle, so don't assume you need two identical shields.
If you really want to try an HH, I think you need the EMP, which means you need stealth and heavy shields up front. They won't have time to recharge if the HH guns target you. Make a pass and I recommend prayer. Take a lesson from our own Marcsand2--know what is shooting at you. If an HH has ballistics loaded, I suggest leave it alone.