You know what they say about pics, they are at least equal to dozens of words..
I had never heard of Broosha Solar before. That looks like an industrial site.
It sounds like you got a good deal. I've seen some Enphase that were really cheap,
but they were 208v, instead of 220v..
$16 a year might be good when you first start and want to keep a super close eye on panel performance.
But, after a while, when things are stable, the data might become somewhat boring.
As far as I know, there is no aftermarket data collection/plotting software.
But, the Envoy has a built-in basic Webpage, where you can see performance and trouble shoot etc..
People have been trying to use that webpage to mine the data, so they can use it with Excel etc..
Enphase Data Access - Solar Electric Power Discussion Forum by Northern Arizona Wind & Sun
If I get into grid-tie, I would likely just use the built-in webpage with an old PC.
From what I've read, it seems like enough data for me..