I use the same Ortlieb rear panniers and Ortlieb handlebar bag on my Bike Friday New World Tourist, as on my old touring bike with 700c wheels. I've never used front paniers on any bike.
After flying with my Bike Friday, I've been able to leave the suitcase at hotels, guesthouses, B&Bs, or with friends. As for trains which do not accept bikes, I bring the largest plastic trash bag sold. I fold up the bike and put it in the trash bag. It's a lot easier to put in the trash bag if I remove the pedals first. My friend (who also owns a Bike Friday) and I did this with our bikes to take them on TGV trains in France which either did not take bikes, or which had no bike reservations available. I was touring in Italy last month and the regional trains all took bikes for a 3.50 euro fee. No folding or bagging necessary. A couple of times, the ability to fold the bike has allowed me to get the folded but unbagged bike into minibuses in Thailand and in Colombia.