If you're on a tight budget or just want to start at the very bottom with nothing to your name then there's the Aurora, which comes in the standard variant (actually the MR, but the details there aren't important) or the LN which is more combat focused with additional weapon hardpoints. However, you may be interested in a 300i (either base model, 315p for exploration, or 325a for combat. Those variants are just different equipment packages though, at their core it's all the same ship) or an Avenger instead as they're a bit of a step up and don't cost too much more than an Aurora.
If you're a bit loose with your wallet and don't mind specializing a bit more the Freelancer and Hornet offer a good choice for a dedicated trader/explorer or mercenary respectively. There's only one option for the Freelancer now, but the Hornet has an additional stealth and recon variant available for consideration, again those variants are just different stock equipment though. At the same price point is the Cutlass, which sort of combines Hornet and Freelancer into a ship that's good at combat (though not as much as the Hornet, though the Cutlass seems to be more maneuverable) and can do some exploration but cuts back on cargo space and weapon hardpoints. Also, some claim you'll be typecasted as a pirate if you fly one but that's not really true. For some reason the Cutlass package isn't available to new backers so you'd have to have someone else buy and gift it to you though. That's a good idea for all ships however, as you can get LTI that way!
Finally if money is of no concern and you don't mind playing with friends or hiring NPCs in-game to get the most out of your ship, the Constellation is the best money can buy. It's the largest ship on sale now and the fourth largest we've seen (Retaliator, Idris, and Bengal are larger). It's role is that it doesn't HAVE a specific role; it's the most versatile ship available and can be equipped to fulfill whatever you want to do with it, even dogfighting despite its size.
