My wife and I stayed a few days in this lovely hotel, when we just arrived in Bangkok.
What we loved most about Phraya Jasaen, aside from the friendly staff and convenient location (5 min walk from the metro and river ferry station), was how homey it felt. In terms of interior, it's fantastic eclectic combination of some traditional Thai, Western vintage, industrial, etc...and the imagination of the owner, who also has his wacky collection of objects and trinkets on display throughout the hotel.
Regarding the room, I'm a very light sleeper, so a quiet room is an absolute must for me and I have to say, our room was perfectly quiet
We didn't have breakfast ourselves, as we basically made it down too late every day, but the coffee shop is cosy and also serves VEGAN. If you're in for something more elaborate, check out the vegan restaurant down the street (you won't believe the menu!).
In short, it was an absolute pleasure and we warmly recommend this little gem to everyone.