I can confirm that the second floor ceilings are very high. Looks like 18-20 foot in both the bedroom and sitting room in the Park Suite.
I stayed here about 10 days ago and was proactively upgraded to a Park Suite on the 5th floor. Since it was a late arrival and just one night I wasn't too concerned about the room but they had Le Labo products in the room as standard rather than Pharmacopia. The room pictured above doesn't look like the Diplomat Suite which we had when we stayed earlier in the year on the 3rd or 4th floor with a separate room for the desk and a good size living room, matching photos on the website. The restaurant is wonderful and I really enjoy visiting. I would agree that the pool is too cold and not really comfortable for hanging out as a family for instance, maybe that's the intention?!
I thought that Monique Dekker had moved on from the PH Vienna, but see she's still there and regional VP now too. She's trained her staff really well.