I moved to AirVPN from Mullvad due to port forwarding alone and have been very happy. You’re not limited to using their software. For instance I’m using the official Wireguard app on Mac. While you cannot “browse” which servers are available within the app, if you only connect to a few servers, it doesn’t really matter.
There was an earlier thread where the client software was discussed and I noted that Windscribe’s client works and has a much nicer interface.
I also switched (from Nord) for the port forwarding but I’m not as thrilled with AirVPN as you are. Mostly because I now can’t get to a lot of websites that detect and block AirVPN and that never happened when using Nord. One example is the government of Canada sites. I can’t even do something as benign as checking the weather if the VPN is turned on. And banking… forget it.
I tried airvpn this month, and have already gone back to mullvad. Running linux, eddie-ui crashes once a day, and seems to ‘break’ apps like conky in a weird way (conky freezes every few mins, doesn’t update for 20 mins or so). The only thing it has that is better than mullvad is the port forwarding, which isn’t worth its 50% increased cost ($7 vs $11 a month).