[@Crimson Raven] Hmm. Sibling pair might be okay, depending on your choice of classes.

As for starting weapons, there aren't any real weapon rankings - weapon quality is divided by material (bronze, iron, steel, silver) and higher materials are more rare but better for enchantments. When I say to be reasonable, I ask what your character would probably have; iron is what you're most likely to have, maybe steel if you're really well off.

A unique or named weapon you start with can have a unique design, but won't function too much differently than a normal weapon of the same material aside from one minor trait (maybe it stays sharp better or is built for your specific fighting style - you would specify when you create it). A weapon that 'gains power as the user does' is probably just a little too much.