If we were doing it again we would buy zero paper travel guides. Lonely Planet is IMO not what it used to be--twenty years ago it truly explained how to do life; now it's basically Fodor's but heavy--and we consulted them basically never.
The Swiss rail pass for 15 days was expensive but genius--we didn't have to prebook anything, it made nearly everything (even the Mont Blanc Express) free and the few things that weren't were half off, and direct booking by trip is $$$$$$.