As an islander, I too have struggled finding a viable internet provider. Have had Hughes satellite for a couple of years. While it works well, I'm not a fan of the data limits. The long latency due to the round trip to the satellite makes video conferencing a pain. It also has had big issues since the pandemic as everyone started hitting it hard and speeds dropped significantly.
I did decide to give Starlink a shot. Its low earth orbit satellite network eliminates the latency issue and speeds are really good (supposedly will improve with time). The issue I have is a lack of really clear northern sky. I'm in "obstructed" zones a 1/4 to 1/2 the time making it unviable. I could attempt to clear trees to improve the view or wait for more Starlink satellites to come online, both of which will improve the situation, but not sure I have the desire or patience for that.
NH Electric Coop has begun rolling out broadband service, but they are doing it in a phased approach over years. Given the infrastructure cost of getting lines out to the islands, I suspect we may be the last ones to get service, if ever.
I was alerted to the (recent, I believe) efforts of Hub66 to bring service to the islands, in particular. It is fiber on land and then wireless to the islands. It's the most pricey option and I've been told the bandwidth you get will depend a lot on environmentals (e.g. tree coverage). I did express interest via a form on their website which I believe will get them to evaluate my location and see what is viable. Keeping my fingers crossed on this option.
https://www.hub66.com/winniislands#signup
-Mike