Think you're bang on TBH. I'll take a trip to the local apple store and compare a few with regards to size and weight and will let that dictateWhat i'd really recommend is a fully-loaded 15" MacBook Air because it sounds like you need the screen real-estate more than you need the power you'd get from a 16" MBP. And it probably wouldn't cost much more than a 13" MBP.
Trouble is, it doesn't exist yet.