I like the amount of thought that you've put into the layout. I agree that there will be a pedestal with meeting space, amenities, and below grade parking. I think that the L will run along W. Temple and on the north side of the UMOCA site, adjacent to Abravanel plaza. This alignment will allow sun to reach the interior of the hotel, which I am assuming will be the location of the pool area, on top of the pedestal.
I could see two towers, differing in heights, one on the SE corner of the site fronting W. Temple, and the other on the NW corner of the site, with the taller of the two towers facing W. Temple. I'm going to say around 475' and 375'.
Just off the top of my head.
Red - Pedestal 4-6 stories tall, takes up the entire footprint. Lobby, Street level retail, restaurant, bar, conference space, spas restaurants, pool and other amenities.
Orange - Traditional L shaped hotel, roughly the same width as the Marriott across the street.
Blue - Hotel Tower 36 stories (ground to top), roughly 475' tall
Green - Residential Tower 28 stories, roughly 375' tall
I'm sure we'll hear certain forumers mocking our enthusiasm, but I look at it this way. Every city that now has beautiful buildings got that first significant building at some point in it's evolution. So since the county is giving land and is requiring great design, this could very well be the tipping point for Salt Lake City.