I had a stay at the Envoy last evening:

The positives: Great location in the Seaport. Especially in the case where you have been to other parts of the city or once lived there, this is a novel area, since it is all new. I would position the hotel as an upscale W vibe, but bright with mostly white or light tones. There is often a line outside the hotel and for one of the elevators as the rooftop bar is a coveted drinking spot. The rooms are modern and nice (lots of power!). I had a corner room, and the bathroom was open and cool (but close-able, if you wanted more privacy). No lounge (a think the offer was $12 for breakfast or 750 points). Even though I get annoyed that every thread breaks down into free-breakfast commentary, I included this so there's no need for folks to ask. Despite the negatives below, I would stay here again as I think the negatives are manageable.

The negatives: I pre-booked a corner, water view room through my Ambassador but was given one where a tree completely blocked the view. In the winter, this would be a marginal item, but in the spring/summer, you could only surmise that there was a water view. I was there for an evening out with the DW (anniversary) and didn't want to fuss. That evening, unfortunately, beginning at just after midnight and apparently due to a movie being filmed the next morning, there were trucks and dumpsters and portable toilets and all sorts of stuff being dumped off and dragged right outside the room. It was calamitous and woke me up just about every hour with some new sound. I know that the hotel isn't responsible for the noise, but I would think they would have or should have been aware that this movie was being filmed and that there was the possibility of noise. Even a pre-warning and a set of ear-plugs would have been sufficient. Separately, the bloody mary's are sub-par.