You can actually become a Paladin? Really? Unfortunately the same cannot be done with the rangers.
Yeah my first playthrough i was a ranger, i guess i didnt feel part of the team. Now im pro caesar and i feel like a monster. My fallout 3 past struck me and i thought hmm... BoS!!!
I did the Brotherhood of the Steel Questline and now I'm a Paladin.
Spoiler
It's really worth it if you're an energy weapons user because they give you free microfusion cells and energy cells when you walk in and look in your trunk.
The trader there also sells tons of stuff good stuff. But I'm disappointed because the questline isn't very long.