Most of my trips are solo, and I've stayed at both PO resorts as well as most of the DVC resorts.
September is peak hurricane season. Odds are that a hurricane won't come here, but if it does, it's better to be in a resort with interior corridors (like most of the DVC resorts) than exterior corridors like PO. If you are in a resort with exterior corridors, and are confined indoors for the duration of the storm (can be as long as 36 hours) you will be cooped up in your room. Granted, on a honeymoon you might not mind being confined
but I know I get restless being confined to a space like that.
With the interior corridors, there may be short time periods where you are asked to stay in your room, but at other times you can walk throughout the resort. Also, with a kitchen/kitchenette, you will have the option to prepare some food in your villa if the restaurants are closed (yes, that happened to us once).
Now, other than the chance of a hurricane, I would still recommend a studio over a regular room. As a pp said, you have a seating area as well as a sleeping area, which makes the room feel bigger. Also, you have a larger fridge, a microwave, and a toaster, for preparing meals and snacks. Studios are a great size for one or two adults, and many of them are in great locations for getting to the parks easily. The bathroom size of a studio is comparable to a regular room.
If you can afford the one bedroom, I would go for it. You will have a king bed instead of a queen size, plus the full kitchen (I love having the full size fridge for beverages and the freezer for ice) and the laundry. Having a laundry in your room means you only have to pack half as much clothes because you can pop a load in any time instead of sitting around a laundromat. I find this especially helpful during hot September weather, when I have been known to change clothes two or three times per day because of the heat. I also like having a free standing shower stall instead of the shower in the tub. September is the one time of year I splurge and get a one bedroom for myself - otherwise, I go with a studio if booking DVC.
There's nothing wrong with PO - but for something as special as a honeymoon, I think I would go with a villa.
As far as which villa, that would depend on what themes appeal to you most. I would probably stay away from OKW and SSR, because those don't have the interior corridors that I mentioned earlier. If you think you will spend more time at Epcot, either BWV or BCV are good choices. BWV is more centrally located between Epcot and DHS, and the boat dock is right at the resort. At BCV, you are very close to Epcot, but you have to walk to either Epcot or YC to catch the boat for DHS. If you are spending more time at MK, I would pick VWL as the first choice and BLT second. The only reason I would pick BLT second is that the studios there are smaller than at VWL - but location wise BLT is closer to MK. If you want to be a little more secluded, AKV is great - it has a very romantic atmosphere and the animals are fun to watch.