If you are going to play EVE for the long haul, are lazy, like running missions for full clears, and got isk to burn, then yes, marauders are a fun addition to your fleet of ships.
With bastion modules, marauders get near immunity from ewar. Saves a lot on mission times and annoyance, and awesome for missions like Dread Pirate Scarlet, The Assault(Serpentis), etc… Especially for ewar like sensor damps which are still at full strength, but ecm got nerfed…
Marauders aren’t necessarily gank magnets either, as T2 fit is overpowered for lv4 missions, and often tougher than blinged-out faction ships that can cost more in the end.
And as someone mentioned above, find the weapon system you like, then the marauder to match. Don’t listen to blah blah blah, Paladin sucks, blah blah… All the marauders perform quite well, and all are overpowered for high sec anyways. It’s more about your playstyle. I prefer blaster Kronos over ac vargur myself.
Personally, I have only found Serpentis to really be worth doing full clears. On Lv4 Assault(Serpentis) I generally get 20mil isk bounties, about matching 20mil isk salvage, and 5mil isk loot. I lazily run that in about 45 min, in a half-ass build Kronos, and hardly use drones. And that’s despite all the crazy sensor damping. That’s about 60mil isk/hr. Someone a bit more hardcore could run it much faster I’m sure.
To sum up, marauders are comfortable “end game” ships, are great for mission full clears with their designed extra utility highs and luxurious cargo space, have great dps and Demi-God-like tank, and a lot of freedom from ewar nuisance.