I'd probably take Venetian at those rates. I've replied to your questions on the WA in the Hilton forum thread you posted in. WA's a nice property (arguably more upscale than Venetian in some subtle ways, like having a valet closet) but they're not likely to give you a full suite just because you're a Diamond (the upgrade from base level room is "strip view")- every room is a 750+ sq. ft suite at Venetian (though arguably a junior suite for a lot of them since the living area isn't walled off from the bedroom).

Also, Venetian's F/B is likely to be a lot more active/available than WA's in mornings, though note that Palazzo (Venetian's sister property) is closed M-Th, so keep your expectations low.