Hey robl45.
Welcome to our Mattress Forum 
Hitting the “analysis paralysis” stage is so normal when mattress shopping, especially because - in your case - you’re trying to combine the deep contouring hug of memory foam with the buoyant, responsive luxury of a Four Seasons hotel bed, which are actually two completely different styles. Hotel beds traditionally use a heavy-duty coil core topped with plush polyfoam and fiber which is why you feel supported on top of the bed and can move around easily, unlike traditional memory foam that can leave you feeling stuck or sinking right through to the hard base foam underneath.
Looking at your top picks, the Silk and Snow Hybrid Plush is a pretty good fit; at 185 pounds, a plush memory foam hybrid will likely cause your hips to dip too much for back sleeping, and the weak edge support will make a king bed feel smaller when you roll toward the sides. The Nectar Premier Hybrid has a thicker comfort layer than the classic so you won’t bottom out as easily, but it still leans heavily into that slow-moving memory foam sink that runs counter to that easy-to-move-on hotel vibe.
The Amerisleep AS3 Hybrid also makes a lot of sense because their foam contours like memory foam but responds and recovers much faster, giving your wife pressure relief for side sleeping while keeping you from feeling trapped and isolating motion way better than your current Amazon bed.
Outside of the folks on your list, the Nest Owl from Nest Bedding is a fantastic place to start because it uses a three-inch layer of Talalay latex over pocketed coils, giving you good responsiveness and excellent motion isolation, plus it features a zippered top so you can easily swap out the foam layer if your comfort needs change as your weight drops. True factory-direct builders like @Arizona_Premium or @Sleep_EZ are also incredible options because they use high-spec, durable materials and allow you to customize the firmness levels for each side of a king bed, meaning your wife can have her side-sleeping pressure relief while you get solid back support.
NikkiTMU