Fares are approaching $400 and in upper $300s round trip for Miami to many cities in France and Spain, and a few spots in Switzerland and Italy.
Low fare travel departures run the entire schedule for Spain Feb-May, Aug-Dec 2017. Star Alliance has some deals to some airports, but Oneworld and SkyTeam are the real action for low fare deals to many airports in Europe out of Miami right now for travel anytime into next December.
Most interesting to me are ticket prices from low $400s to $500 round trip to many of these cities for travel in June and July with both Oneworld and SkyTeam airlines and then all kinds of deals for August and September late summer travel.
To get a sense of how good these deals are for summer travel, Star Alliance is not discounting summer season ticket prices at time of writing and their routes are $400+ more to Barcelona, Madrid, Milan, Ibiza and Palma de Mallorca.
Google Flights maps show the geographic range of low fares.
American Airlines Miami MIA – Madrid MAD – Miami MIA
British Airways Miami MIA – Paris CDG – Miami MIA nonstop
Air Europa Miami MIA – Madrid MAD – Palma, Majorca PMI – Madrid (overnight transit) – Miami