The thought: "Maybe something else is better."
I don't think you're going to find anything significantly better shopping elsewhere.
On CDF you mentioned the following list
ScubaPro, Apeks, Atomic, Deep6, HOG, Poseidon, AquaLung
The Deep6 are an improvement of the HOG design and have a lower total cost of ownership due to first free service and if you take the reg repair course the free parts every year. That rules HOG out.
Atomic is part of the Huish and that rules them out for me immediately because of the horrific customer service associated with that company and all of their subbrands.
Scubapro is great, but is a bit of a rip off IMO and is also an unsealed piston which I'm not a huge fan of.
Apeks are irritatingly expensive, you can't DIY service without a "hookup" for parts, and the DST doesn't come with the bottom port so you have to spend more to get that which comes standard on the rest of them.
Aqualung doesn't have a swivel turret and has the same parts issues as Apeks since they're the same company.
Poseidon is phenomenal, and my preferred regulator, but they have a unique breathing characteristic that is rather polarizing. for most people. You either love them or hate them. The first stage is brilliant, but doesn't have the best hose routing options without the swivel, or the bottom port. The bottom port is IMO critical for doubles.
So that leaves Deep6 and Dive Rite. I think the Deep6 regs are better, but then you will have two different regs to keep maintained. If that's not an issue for you and you're buying new, then they're going to be the better "buy" IMO but if you're looking for an improvement, it's going to be splitting hairs vs the XT1's if they're tuned properly.