Having just moved to a new house that's only served by OFNL, I searched through the list of OFNL ISPs to find one that didn't seem to be just a basic reseller. Luckily I found Merula. Their website describing their service is frankly not great, and I had to email them to get the fastest speed (900/450) added to the online ordering service (which they did promptly).

However for that effort, I got a very fast connection that comes with a static IPv4 address, and a /56 IPv6 PD block (plus an extra /64) for a reasonable price (about the same as the other OFNL providers). I did have to email them to get the static IPv4 and IPv6 addresses enabled, prior to that I was getting an internal IPv4 address (likely CGNAT), and no IPv6, but that was sorted out very quickly.

I did have an issue initially activating the service, but that was caused by the OFNL hardware which they needed to get an OFNL engineer to visit to replace the ONT. Once they did the service came up immediately.

All my interactions with support have been with technical knowledgeable people, and even the director Richard stepping in to nudge OFNL to do something.