I'll start off with a bit of philosophy then hopefully give you some useful tactics.
When I was young, lots of people I knew were 'writing' table top role playing games. Yet, almost to a tee, when I would accept the invitation to 'play test', I would show up to a description like:
"Yeah, we have dice and the coolest magic system you have ever seen, but it's not done, but I photocopied character sheets from AD&D."
It got to a point that by the time I was 18, whenever I was asked to play test a new game, my stock response was, "I'll help out when it's ready to be released." I wasn't exactly Mr. Popularity at that point in my life so I don't have a large sample, but my friends all had very similar reactions.
Roughly 25 years later and I know lots of people who are working on board games. Is there any chance that 'the project isn't finished' scares early adopters the way 'I'm writing a game' scared me?
I wonder if changing your pitch would help. Maybe instead of saying 'the project isn't finished', you could say that you're play testing and balancing? Sometimes in early stages, selling is about telling the truth in a more palatable way.
All that said, this is actually a pretty good marketing campaign. At this point, your biggest goal is one fan. You could spend a lot of money on marketing, but that's not worth as much as one person saying they played your game and loved every moment of it.
In my experience with board games, social proof is very important. You could spend millions of dollars on marketing and I won't play your game. But, if one of the people I trust suggests it, I'll be there.
So, at this point, think of ways that you can get people to play your game and talk about it. The talking about it is just as important as the playing.