It's easy to get analysis paralysis with analytics, because pretty much anything can be measured now. You'll need benchmark analytics like visits, pageviews, etc; then you'll want key performance indicator (KPI) metrics that change over time. The KPI stuff will vary depending on what you think is important for users to do. For instance, if you were an e-commerce store, then you'd want to look at cart abandon rates, conversion rates by category, traffic by category, conversion rates by traffic sources, week over week revenues, 30 day daily average, 90 day daily average. For cohort analysis and anything money related, I've found custom sql queries displayed on a reporting page isn't too hard to do, and it's great when your KPI's change or you want to add more into reporting later.