Hi, OP - I totally get where you're coming from. For my first solo trip, I splurged on the Beach Club because of the interior corridors issue. When I decided to make annual solo trips, I needed to cut $$ so tried POFQ (exterior corridors). I was uneasy about it before I went - but once I got there, I fell in love with POFQ!!! I have stayed alone at POFQ 4 times and always felt comfortable.
Where the concerns about inside/outside corridors come from is the "non-WDW" world, where lodgings with outdoor corridors are cheap motels on the highway where anyone driving by can pull into the parking lot and bang on your door. You will be at a Disney Resort, which is a much different environment. Use your common sense safety precautions, but tons of WDW solos stay at all the WDW mod and value resorts safely and comfortably.
I may be in the minority, but I feel more comfortable walking to my room at POFQ, where I can see my building/ corridor / door well before I get there and there are plenty of people within sight/earshot, than walking alone through a long, winding interior corridor with no one else visible.
If I did stay at CSR, I would book a preferred room to be closer to the main building. If you haven't considered POFQ, I highly recommend it.
I will not stay at Swan / Dolphin because I love Magical Express to/from the airport.