There are detractions, but you can't deny the history of the place deserves a visit.
I haven't been for years, as the most recent trip had to be cancelled. However we had planned to use the Novotel Marseille Vieux Port, which is a full facility 4 star with a pool in season & secure parking garage (c.21 euros). Just float some dates through the Accor website, or booking.com if you enjoy member benefits.