If I were you, I would just go straight to law school. I don't think either a master's or a year working would be more beneficial than having that extra year of practical training in IP law in a firm. I've spoken to patent lawyers at one of the big Pharma companies, and they advised me to just go straight on to school because companies care about you as a lawyer, not as a scientist. I don't think the master's would help that much because there are a good number of Chemistry Ph.Ds going to law school and from my experience working in industry, master's and bachelor's degrees are pretty much equivalent, so I don't know that a company looking to hire a lawyer would care that much that you had a master's. You have some great law school options right now, and I think coming out of one of them and getting to work would help much more than delaying.