As a maintainer (and product owner/pm) of OSS, I somewhat disagree with the OP. Beware of your over-attachment to a project that others are willing to contribute their ideas, time, and energy to. You are not an oracle; nor are you the only user of your product. Other people have better ideas than you do sometimes, especially when they're your users.

Give them latitude to take the project in ways you disagree with, even vehemently. Your project will be better for it, and you'll learn something along the way.