We stayed there for two nights. We used our Marriott Suite Upgrade and were upgraded to a King Suite. The rooms looks similar to your 2nd photo. We had a small entry way that had a closet to the right and a credenza to the left that held the coffee machine and a free bottle of water. Then about 2 steps in, was a sitting room with a table and small couch. (That is where both of us stored our luggage. You could unpack and use the closets, which we did). Then we had the bedroom which the bed takes up the majority of the space. Small "hallway" with a closet to the right and then your entrance to the bathroom to the left. The bathroom was spacious - shower, no tub. The rooms are small. If you need a lot of space, you will not be happy. HOWEVER, I will say that the staff did a great job with us. Our toothpaste was "confiscated" by TSA in Brussels, so we were stretching a tiny tube we had with our amenity kit from the plane. We returned to our room and found two tooth brush kits that included toothpaste. The staff did a nice job anticipating.
Having said that - I would say that the service outside of the room was spotty. The breakfast was free for Titanium Elite if you selected that as your gift. There was a nice selection of food. Our favorite part was the bartender in the bar. That was the best Manhattan I have ever had in my life.
It is Venice. You don't want to be in your room and the sitting areas around the hotel are many and beautiful. There is a private courtyard with an amazing view of the canal. I'm sorry we did not take any pictures of the room, outside of this one.

Taken standing near bedroom entrance. Can see table and open area where the front door is.