Hi there,
From what you've said it sounds like you've chosen some pretty good options, and great to see some city options in there too as these are generally more suited to a varied social life in the city.
Polden I would say is relatively sociable because its quite separate from the other accommodations - as long as you make an effort to engage with people and keep your door open I'm sure you'll quickly get to know the flatmates on your floor. Green Park House, Scala and Thornbank are all good options because they're very close to bus stops and the centre and so people from these accommodations tend to do more in the city together than people in on-campus accommodations. John Wood is a very sociable accommodation, its only two minutes walk from the centre of town and its quite small and open meaning you can get to see people often.
Quards have a reputation for being the most sociable on-campus accommodation due to the fact that each Quad floor has a shared lounge/zen hub with modern decor, and big kitchens where people generally meet up and have games nights. Woodland court is a really nice option in a peaceful side of campus near the trees - there is outdoor seating areas where you can sit and chat/have a picnic in warm weather and the rooms are again in floors with flats up the corridor, so it is indeed conducive to bumping into people between lectures.
Other sociable accommodations are any with non-ensuite options such as Westwood, Eastwood Green/Terrace and Norwood House.
I hope this helps! Best of luck with your next steps and hopefully you get the option you want 🙂
University of Bath