I find myself consistently disappointed by Westins. There are two I really like: Crystal City and Boston Copley so I've been trying to stay at more to replicate the feeling I get at those two hotels. However the ones I seem to end up at, Las Vegas, Pasadena, the awful New Orleans Canal Street etc. feel like Sheratons at double the cost and like the OP I don't find much in the way of benefits, certainly not to justify the often inflated price tags.

No, a Westin is not a "benefit desert"
 

Westin is one of my favorite brands.

Many (not all) have a contemporary design aesthetic that I like.
Westin was a pioneer in using scents to add to the guest experience. That may sound trivial, but so many emotions are triggered by smell.
You can't beat their Heavenly Beds.
You can't beat the quality of the towels.
Their bathroom soaps are chemical-free and not made in China (yet, I'm sure Marriott is looking to change that).
All properties have made a commitment to having healthy, super-food items on food menus.
Starbucks has been their in-room coffee for ages (Marriott and Renn have what no-name brand in cheap coffee makers?)
Almost all Westins have a full-service restaurant, often a destination restaurant if in an urban area.

I understand that legacy Marriott customers are used to the value aspect that their brands offer in terms of free breakfast or lounges, but Westin has never tried to be in that space. The SPG option of breakfast was always available and satisfied me, but again my preference was quality over quantity.

well I seriously doubt that

Sad the White Tea products have already been Marriottized/Bonvoyed

I confess that except for Bliss Products at the W, the toiletries at the various Marriott full-service properties, as well as the Hilton and Hyatt full service properties I can't distinguish any particular difference in quality. What is the difference between Thann, Asprey, Aromoatherapy, White Team, Aveda .... As for manufacturing in China, that may be less of an issue as hotels move away from single use plastic toiletries in the room in favor of dispensers.
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But back to the issue on benefits

1. Upgrades vary by property. In general, I've had better luck at legacy Marriott properties compared to Westins. But part of that is that I may have go to Marriott properties that I know will upgrade me and avoid those that don't. i've had bad upgrade experiences at most of the Westins I've stayed at (obvious lies for example at Westin La Paloma, refusal to upgrade but not lying about it at Westin PVR, and the hotel designating a couple of rooms as standard suites in other properties but good luck at Westin Boneventura and Westin LAX so its really a matter of the individua. property. Sounds like Huntsville, like the Alexandria Westin, is resting on a great location to skimp on some benefits.

2. JW/Marriott/Renn almost always have lounges; some Westins do. For properties with lounges, I can get breakfast, a dinner snack, and a $10 voucher or 1000 points. From any objective perspective, that's a better option than the Westin plat option that requires me to choose, as opposed to getting all three. If its a resort, its a tougher call.

These aren't benefits. These are either the same features every full service hotel has or really minor features (scents, really?).