what country are you in? I’ve not encountered Sony PA/sound reinforcement speakers myself (at least in Europe) they always concentrated on home hi fi and by and large smaller portable pro equipment rather than “big stuff”. it is more common to find small Sony audio recorders and professional video cameras That is not to say these do not exist in some markets as in 1994 Sony took over Aiwa in Malaysia which made a lot of semi-pro equipment.
as you have realised you are not going to be able to fill the basketball court with the available resources/budget; so maybe concentrate on a corner/smaller area of it.
if the safety/zoning permits see if you can get the harsh strong lights shut off so they do not overpower whatever lighting effects you bring along.
it may be worth signing up to the “all ages” site partyvibe.com as a lot of pro sound engineers and event organisers lurk on there and maybe can give you better / more specific advice as it was about 10-12 years ago when I was more involved in these sorts of events (lived in a small town/aspiring city called Reading back then which was a lot like “British Seattle”)
There was a crew called Itsy Bitsy which specialised in filling the smaller areas of big warehouse raves etc and put a lot of effort into the décor/getting good quality sound into a small space. (Edit: looks like they are still about 🙂 )
