Yesterday while I was cutting some nails, I noticed my albino, Bino, has much smaller nails than the other 3. Is this something that has to do with being an albino?
By smaller, do you mean not as thick/can safely be trimmed back further? If so, that's most likely an indication of a history of frequent nail trims - if any of your rabbits tended to go a while between trims before you got them and Bino didn't, their nails would appear larger.
As the nail grows out, the quick grows out as well, limiting how far the nails can be clipped back - the only way to get the nails to be "smaller" is to trim small amounts off of them very frequently (every 1-2 weeks instead of the usual 4-6). Every time the nail is trimmed a bit, the quick recedes a little... making it possible to trim them back a little more before they've actually regrown to their original length. Eventually, the nails will appear smaller and shorter after being cut just past where the quick stops because the quicks will have receded to their original lengths .