Most of my trip planning was plagued by the DBbahn.de. Yes it is comprehensive (too comprehensive, which website can tell you what time to take the bus from a remote bus stop where you don't know where it is, and then take the train then find another bus from another unknown bus stop) with lots of languages. I wished it showed the layouts of the routes, or train stations for choosing by people who have never been to Germany, really shitty grasp of direction or language, instead of assuming that we knew what bus stop or train station we were going to be staying nearby. You can book train tickets for others, and state that their credit card will be the means of verifying their identity. B1 as usual, left it to me to do the planning. This year the excuse was, to quote him, "Germany is you want to go one, not me. I'd be perfectly satisfied with Taiwan or Japan (his two favorite sources for ogling pretty Asian girls)." So I tagged his credit card, since I have always resolutely never gotten a credit card, even after working.
Then there were the options, first class, second class, with discount (then which discount), cabin or open salon, special discounts (SchönesWochenende anyone?), seat reservation, bringing pets or bicycles? Oh ja, we ended up using the group travel ticket (~29euros) very often. It was really worth it, you can bring a family of four and the dog (party of 2-5) along.
One thing I did regret was not confirming the ICE tickets early. Massive price jump the nearer you are to the date. The other stupid thing was after listening to my colleague's recent travel experience in Europe (about how he was robbed 4 times, once on the train), I chose mostly open salon seating, instead of carriage. Massive mistake man, because the seats were awfully cramped. However we were totally left alone on the train and people were actually friendly to us when we talk to them or they want to help.
Carriage is cool. you can stretch out and do funny stuff inside, like pose your forever smirking bear near the window. =D