To provide a quick update on this topic. After enquiring about a potential replacement amenity for the high-speed internet included in the resort fee, I was informed that the resort fee would be optional for me on a daily basis, i.e. I could choose to pay it or not. They actually had quite good benefits listed in the resort fee, e.g. some hydro-massage treatment in the spa and andean bread baking / cocktail tasing and some more activities I am forgetting. I did not end up using any of these benefits as I was alone and mainly wanted to relax in the room, but it actually sounded like good value.
Overall the hotel displayed the best ambassador appreciation to me since the merger of SPG and Marriott. I had already used SNA to receive a confirmed upgrade to a Junior Suite (Senior Suites were not in the pool) and the hotel was quite flexibel about late check-out. The front desk agent told me that it would be difficult to grant late check-out for the Junior Suite, but if I were willing to change to a normal room on the day of check-out I could "stay as long as I want". I ended up staying until 6pm without any issues.
To me the hotel had a similar feeling as the Prince Gallery Tokyo - for only 35k points per night I think this is one of the best award redemptions out there.