IMHO, startup communities are the worst. Most of the great startups I know avoid those communities, and are usually already a part of 500 Startups or YC.
It's also really common in these communities to post nothing of value. Everyone asks for opinions, takes a month to post a landing page, talks about an upcoming huge launch, repeats this once a month.
As a result, they get very jaded and cynical, the exact opposite of what entrepreneurs should be.
It sounds like you think you know who you want to target and think you know the value you provide them. I'd encourage you to try to make your first few sales manually, before trying to tackle the channel acquisition problem. You can't scale a channel before you know who to target and how to sell to them.
Good luck!
This is anecdotal, but I found it much easier to tweet something to someone 8 years ago, and get some feedback. Now, you're lucky if you get a response back.
People want their problems solved.
I care about the quality of the product and support