I feel like the home screen just shows me markets I've already seen many times. It's not very helpful, except for the occasional boost.

After market close (six months) I will open the home screen on mobile and scroll through the first 30 markets I see. If 6 or more are unfamiliar to me, market resolves YES. 

For this last one, note that I get notifications for comments on markets I've bet in, and I check my notifications before the home screen. Also, I tend to monitor big swings in my own portfolio. Both of these make it less likely that I won't have already seen new developments. 

Sister market for a shorter timescale: is the home screen actually as bad as I think it is today?

I will not bet in this market, as it's unverifiable and subjective. 