Why wait?
No, really?
It is not pay to win. It is not subscription based. It is in constant development (yeah, I agree that there are things which need to be fleshed out), but things are getting better with every update.
Instead of wondering if you should buy it, go buy it. Try it for yourself. Find your cup of tea. You have clearly done the research, and lurking in these forums for years you propably have a good idea of what this game is all about.
Want to make this game better? Buy it. Give constructive criticism. FD has proved that they read the forums many times over, but they cannot satisfy every costumer to even the miniscule of details. I like to think that they have a "the whole is more than the sum of it's parts" approach.
Buy it, try it, and if you are still disappointed, leave it, and wait for a patch. Then try it again.
That's my advice.