As a fan of WWII style battleships, I *love* the Mass Driver. A big, slow heavy cannon with a quick projectile that just crushes things. As such, most of my ships use at least one of them. A Scythe with 2 mass drivers, an HV50, and 2 Vulcans is a very beautiful thing. The one downside is that you have to be a good shot to make those ships work well.
As for the ships I favor, I like the Scythe as a general frigate. It's fast, it hits hard. It's pretty fragile, but for a light frigate that's to be expected. Defiant-class attack ships are a main part of my destroyer fleet, along with Vixens for long-range punch(watching four of them loaded with 3 Pilum LRMs send out huge clouds of missiles is terrifying sometimes.) and Toas for support. For cruisers, I favor the Ares mostly 'cause it can fit a lot of mass drivers on it and be pretty much a WWII-esque capship.
I tried running with the Titan once, the imbalanced weapons makes it a pretty difficult ship to fly. On one hand you have a medium mount pointing one way, and the other, you have four small mounts pointed the other way. Haven't done much with the Aurica yet. I also love the Antares, and wish its big mount wasn't a missile mount(I guess that's why I custom-modded a variant for myself which the two missile mounts got changed to universals...)
At any rate, those are my thoughts.