I've actually been thinking about this quite often recently. I'm not very active in playing on the servers, mostly because I don't play video games much anymore. However when I do, it's with one of my best friends over LAN.
The installation system is honestly a pain. I reinstall the game time to time as I've found it cures most of the issues I have with it. But reinstalling it is such a time consuming thing to do. And, like what was mentioned, it's hard to get anyone interested because it's such a hard game to get into, it takes a lot of work just to get playing. And in this world of high speed, it's hard to convince someone to try playing.
But if there's a question as to whether that would actually change anything, I have examples to support my point. I've gotten three people into FH2 (mostly offline players, too, as we live in the country and internet isn't the greatest out here) by installing it for them.
This is such an incredible game, one very unlike anything I've ever seen. It has such high quality maps, models, gameplay....you name it. And I believe that it needs to be more accessible. I know that there are technical difficulties with this, and that the focus of the limited developers is elsewhere, but I believe that it is a worthwhile endeavor.
Something I'd also be open to, although I don't know how to do it or how to make it most effective, would be a crowd sourced publicity campaign. Advertisement. One thing about working so damn much is I've got enough money to support things that I love, and FH2 is something I really want to succeed. I want to see it succeed beyond the successes it has had.
So, yes, I vote standalone. Within reason, of course.