You can select multiple hotels via the "Create a custom trip" link. Is BAH worth the faff to stay GGL? I'm willing to play the game this year and use BAH when (1) adding a night or two at airport hotels doesn't hinder my schedule and (2) when visiting a location where I don't have any hotel status/hotel status isn't really worth anything. At the end of the day though, if I had to choose, I would lean towards retaining my hotel status (free upgrades, quiet rooms, etc) over retaining GGL.