I've reached the point now where I have to start looking deeper into user behaviour and try to optimize the trial-to-paid conversion rate.
I was conflicted as to whether this counts as a "milestone" but I think it is - I'm no longer in the early stages where I'm just looking to drive any traffic into the top of the funnel and hope for the best.
Now I care about my conversion rate! That means I want better qualified traffic and I need to start making improvements to the individual steps in the funnel.
Huge improvements to be made in terms of getting users from step 2 to step 3... but actually my core focus for now is optimizing the funnel from Step 4 to 5 to 6, it feels like those users are already highly qualified so I have a better chance of converting them given the right signposting / messaging.
And of course, since I'm an Open Startup I've added the conversion funnel chart to my /open page. Hopefully this helps other early-stage entrepreneurs understand what sort of data I'm looking at in order to make my decisions. I am not looking at any private dashboards - the /open page is all that I look at!