My boyfriend plays an Ophelia crew, and this is his response to seeing your questions:
Ophelia is a far less unpredictable crew; Pigs are good if you want chaos, and Ophelia gives a more unified team playstyle. If you get any Gremlin crew you'll want Slop Haulers, and if you get Ophelia the Young LaCroix are good. The Pigapult is something I haven't tried yet, but if it looks like fun to you, that's what counts. If you get Somer you can summon a large supply of Bayou Gremlins as ammo for the Pigapult, and with Ophelia you can hurl Pere Ravage across the field to explode right in your opponents faces.