Also when it comes to battleships, the stats on the wiki are deceiving. There is a big difference in size of the ships, and lots of other little things like turret placement and arcs. My personal view is that in general the small-sized medium BS's are the "best" (Red Hessian Battleship, Liberty Dreadnought, Bretonian Battleship) against a pilot of similar skill once you are accustomed with the basics of battleship PVP.
I have a GRN Battleship and it is a PVP-magnet. More or less all of Sirius is hostile to you, and a lot of players like to shoot at you as soon as they spot you. It's great for action and it's a fun heavy battleship with a few tricks up its sleeve. All of Gallia, the Tau's and the upper parts of Bretonia is your playground, but you shouldn't take it to Kusari or Liberty.
Capital ships are bad for exploring all of Sirius - all houses have RP restrictions in place for foreign capital ships. A gunboat is a much better choice for exploration. If you want to explore non-house space in a capital ship, Zoners are the way to go. However there's not a lot of PVP to be had on a Zoner ID. An Outcast Battleship or Dreadnought have a very generous ZOI and ample opportunity to PVP - you can take it to a lot of places, but will get RP trouble from some Outcasts for taking your ship to places like Liberty.
Hope this helps clarifying some of your questions. You are welcome to drop me a PM.
