It's designed as an NPC class, so it is underpowered. You might take a look at 3rd party books for some options. AEG's Swashbuckling Adventures has a Noble Core class that might work. I haven't looked at the Nobles Handbook by Green Ronin, but it too has a Noble Core class. As far as balancing out the Aristocrat for a PC class, I don't have any solid ideas.