I think it's *really* personal - we don't spend much time in our room (typically), so for our family, we often prioritize things like access to parks or Disney Springs (one of the reasons we LOVE to stay at POFQ; we make up excuses to ride down to Disney Springs LOL) or dining experiences (like Hoop Dee Doo or the Boathouse) or other additional experiences (like fireworks dessert parties) over a bigger, fancier room with features we probably won't use (but I guess would look cool on Instagram?) But, like I said - that's a really personal decision.
I don't know what typically goes on at POFQ on NYE; that's our anniversary (32 years this year!) and we typically stay home; our favorite time of year to head to WDW is either just after Labor Day or just after the New Year...
Personally, I would look at that extra money to stay at BLT, and say to myself "Hey, what else could we do with this money at Disney to create some cool memories...?" simply because that's how our family approaches our time at WDW.
Whatever you decide, I hope you have a wonderful trip!