Ask HN: When should you launch your prototype App?

I am trying to get users to beta test my app, Hashtag for Emails (www.sharemoto.io).

There is a lot of features/fixes to be made such as: 1. Currently, emails are stored in my database and server, so I have access. The central storage allow for ease of sharing content between users. In the future, emails would be stored in the users' devices, and pass along to one another.

2. Right now, user friction include hashtagged emails must also be CC or send to x@sharemoto.io, for the central hub to receive a copy. In the future, with user permission, I can scan their Inbox for collect all hashtagged emails without author user remembering to CC a copy to my server, much like Tripit's itinerary scan.

3. Re-do UI designs. (new mockups www.garyyauchan.com/sharepoint-for-emails#gallery-311-2)

4. Fix various bugs

However should I make all these changes before launching and getting beta users? Should I just ask more of my friends to test it first? Or should I launch soon to collect usage and patterns - really confirming validity - while (or before) working on these above issues in parallel? Would I receive lower App rating if these issues are not fix, and those having problem re-launch the new version?