OSS analytics packages are unfortunately such a rarity - Piwik seems to be the only serious game in town. All I really want is an anonymized picture of feature uptake and some inkling as to how well we're doing in the UX and perf departments. I want to have these things without that annoying EU cookie widget, without shipping any data to third party services, and without loading any third party scripts.
Unfortunately this seems to just be the frontend tracker, and the backend will remain a closed MS service.
Snowplow is a bit more generalized than just Piwik, and it shows in Piwik having a more robust featureset for website analytics specific. But Snowplow has a lot more usefulness if you're having to merge a bunch of data sources together to get a picture of what's happening.