A terrace where you bring your own coffee or glass of wine---sounds like a person after my own heart! I always looks for a place with a balcony or terrace, either private or shared. The evening glass of wine with a view is part of our Europe experience, not to be missed.
We spent three nights at aaHotel Jazz in Barcelona in April and I cannot speak highly enoughnof the hotel. The location, a block from Plaça Catalunya was perfect ( more on that later). And yes, it has a rooftop terrace with a swimming pool ( and maybe a hot tub as well but I do not recall). We took our own wine up there each evening to enjoy the view before heading out to dinner. This was at the end of April so the bar up there was not open. I don't know if you can BYO when the bar is actually open---but it may not be in October anyway. People were enjoying the pool on each occasion. We did not take coffee up there as the room had no in-room coffee maker ( these seem to be a rarity in Spanish hotels). The hotel breakfast was quite expensive so we preferred to go out to a little coffee bar nearby, alone would in Italy.
As for location, Plaça Catalunya is pretty much the center of Barcelona. Airport buses go directly there ( although the previous stop, Universität, is closer to Hotel Jazz, so get off there). It is at the top of Las Ramblas and the start of the Eixemple. We walked everywhere from the hotel---down Las Ramblas, through Bari Gotic, along the the beach to the Gehri sculpture, up Montjuïc and back, and to Sagrada Familia. The only place we didn't walk was Parc Guell, but Rick's directions for the Gaudi walk from Sagrada Familia to the hospital and then the bus were easy to follow.
Barcelona is very pedestrian-friendly and wonderful for walking. The Eixemple has broad tree-lined streets with a pedestrian path in the middle. The traffic is well separated from you and not intrusive. And the Bari Gotic has pedestrian zones. And then there is the path along the beach. It's all good.
About street noise---Hotel Jazz is between two major streets but it faces a small pedestrian-only square and all the rooms face onto the square as well. There was no street noise nor did we hear any annoying drunks late at night as one might in a pedestrian area. Some people who stay there mention the rumble from the metro below. Ask for a room high up ( we were on the 6th floor) and you'll be fine.
We paid 130 euros a night for a nice double room. Their website is down right now so I couldn't check prices there, but Booking.com is offering 5 nights in October for $909, or $181 a night. That converts to €133 ( checking today's rates).