As long as you use Dolphin there will always be upgrades. BoonEx will not sit on their hands because of our own free will we purchased mods that has nothing to do with them.

Here are a few things to consider when buying mods for your site.

1. Will the developer continue to update it as needed?
2. Are you willing to take a lost if they don't and the mod becomes obsolete.

I think for sites with heavy moderations you should be happy were you are... who says you have to continue to upgrade.

Maybe see more you could keep the site you have and start a new one with the new D7 if you really want to use it.