Yes, futures data is on the roadmap, however, I do not have any kind of ETA to expect at this time. Our options products have been released, you can find the details at polygon.io/options. We're very close to releasing quotes data.
There is also a free API from NASDAQ website but it only goes back to 2012, you can also get split warnings with this API: https://api.nasdaq.com/api/calendar/splits?date=2022-10-20