Many thanks for all your input. We're only going to stay in the NY for a couple of days, we've both been there in the past (although not together). We just figured it would break the travel up a little.

I think we're going to fly into SF, hire a car and probably head south. We're going to try and book some flights this weekend and probably sort a car out too. Still not 100% on what we'll do and where to go, bit more research I think.