I'm always wary of people that freely give advice/suggestions because they probably:

* lack information

* have a conflicting vision

* are being dishonest

I'm not a founder but I imagine that being integral to your own vision is the way to go. Attempting to cater to the conflicting needs of a diverse set of users isn't feasible for a startup.

But anyway this isn't valid only for founders but also to life, friends and family.