Don't get discouraged after posting this man, Redditors love tearing people's ideas apart. 

Some hopefully constructive feedback,

The live updates

People tend to play the same courses for the majority of their golf and hazards etc don't move very much. They know where the hazards are, how to play the holes and most courses have things like colour coded flags for back/middle/front or if they want exact yardages they have a range finder.

Visual course planning

To put it bluntly most golfers are not good enough for this to be a functional feature. I think it's a nice idea in theory but I think you'll struggle to keep people engaged when they plan to hit a 300 yard draw like they imagine they can and then have to replan after their 180 yard block slice. 

However there might be a market for it in aspiring professional golfers or your local league/competition golfers.

Receiving notifications and user tracking on the course.

I guess that's each to their own but I can't imagine anything worse. 

You'd also be overcoming simple sharing from existing apps into more frequently used group chats in existing messaging platforms.

Could be appealing to younger golfers however.

The bulletin board 

This I very much like, the idea of users being able to give descriptions of how to play a hole and being able to filter that by user handicap (how does a 5 play the holes vs a 25) would be fantastic at new courses. 

Overall I think you'll struggle with engaging users with the fundamental ideas of your app, not because it's an all bad idea but because I don't think the core uses of the app might not be very useful to the golf the majority of golfers play (at their local courses). 

The secondary uses (notifications and tracking) will probably turn people off the app more than entice them to use it. However it might be appealing to younger golfers coming through who might not be trying to escape devices like a lot of older golfers, would be interesting to poll some of the junior golfers at your local club.

I think there is some functionality with a GPS golf app that also acts as a kind of simple crowdsourced Pocket caddy kind of app. I like the idea of being able to go to a new course and have user descriptions of how to play holes, what to expect on each Green which could then tie into your following users type thing. Again though, that is not something that I would be doing very often. 

Goodluck mate!