Oh nice one, those are a few areas I know fairly well, so will say what I can.
1. Major attractions? I know about D-Day beaches, Mt. St. Michael, cidre tour, Breton festivals but what else?
In that particular region? The walled town of Saint-Malo is great, as is the old town of Dinan and the port of Cancale. It's very well known for it's beaches, although the weather is... unreliable even in summer. And Breton food is fantastic, the galette (savoury pancake) is the classic speciality of the region, but you can't go wrong with the seafood generally, even if spring is too early for mussel season.
Further away in Brittany, Concarneau and Vannes are attractive old towns; the golfe du Morbihan is pretty, but mainly an old people hangout. Forêt de Paimpol is nice for the old Arthurian legend stuff, and Fougères has a pretty cool castle.
Other than that, you've got the Bayeux tapestry in... Bayeux. Rennes and Nantes are great towns for a night out, Nantes especially has an amazing cultural offer (museums, castles, music, cool bars etc...) and I would really recommend it
2. Is Paris worth spending the time/money? It is compared to Rome but people I know who've been to both say Rome is much better (been there, was GREAT).
It's worth it, but maybe not if you're on a time limit. I mean, all the famous sites are there - hardly need an introduction. Other than that it's got its moments. Hanging round Canal Saint-Martin is quite clichéd, but it is genuinely a nice area; La Goutte d'Or is increasingly gentrified, but still has a multicultural bustle that is quite cool. I wouldn't prioritise it pesonally though, and would stay the hell away fom the Champs-Elysées.
3. Beyond castles and wine, what are the main attractions in Bordeaux and the Loire Valley? Same for the parts between Paris and Switzerland?
The Loire valley I know less well, but for between Paris and Switzerland, it depends which route you take. If you're heading in the direction of Geneva then Beaune has a spectacular old town (and, yes, wine); Lyon is worth a detour; and you have the Jura mountain range. The motorway that goes from Macon to Geneva is spectacular - a series of viaducts running over mountains and lakes; I'd recomment stopping off in Nantua, which is a small laskeside town with easy access to the hills. Annecy is slightly out of the way, but also has an amazing old town/restaurants/bars and a series of canals that run into the lake with alpine view etc...
If you're heading towards Zurich - then Dijon is worth a visit, it's only slightly out of the way to Colmar, which is a major tourist draw with a cutesy old town. Besançon doesn't have a great reputation, but it's also got a really stunning old town on a bend on the Doubs river.
4. What about crime? Racism?
Various non-white friends have commented that France is one of the worst places in Europe for casual racism. As in, naive or patronising comments along the lines of "oh, but your complexion is so pretty!" or being congratulated on drinking alcohol while arab are pretty common place.
Crime isn't bad - stuff like pickpocketing in the tourist areas, but usual rules apply. If you go to Dijon, it has had a recent issue with drug related gang violence, but generally that sort of stuff is restricted to banlieues and only reeally happens between people who already know and hate each other, so isn't something that would affect you. There has been an issue with Chinese people being targetted in some lower income Paris suburbs because "the Chinese are rich", but those aren't the sort of places a tourist would visit, so not worth worrying about.
People will insist on trying to use English with you, even if you speak much better French than their English.
5. Are there any taboos and such I should avoid as a foreigner?
6. Anything else I should know?
There aren't any major taboos that would be particularly unusual to someone coming from a western country. Don't be put off by the Parisians, who are notoriously unfriendly and unhelpdul ("
non, ça ne va pas être possible" is basically the national motto, their not being rude to you because your a foreigner, there just like that with everyone). People outside of Paris are generally much friendlier that the stereotypes suggest. If you speak French, any grammatical mistakes you make will be fairly explicitely corrected, especially if you get the gender wrong ("oh, UNE part de gâteau"). Don't worry about it, they do it to each other too - nothing makes a frenchman happier than the chance to prove he's cleverer than you.
Also get ready for a whirwind of acronyms or childish diminutives too. Why call a train a train when you can call it a "TGV inouï"? or why say "train pass" when you can have a "NaviGo"?
Travel could be tricky if you're planning on using public transport. Generally, the big cities are easily accessible and have easy to use tram networks; but the moment you get away from them, you'll find yourself relying on the TER regional trains or busses. The service is generally not
bad, it's just that trains/buses are infrequent and have a habit of only going part of the journey. So you could find yourself spending large amounts of time in small town train stations waiting for one of the four trains that bothers to visit each day.
France doesn't have a particularly developed hostel scene either, which could make accomodation tricky at times, especially if you like to use hostels as a way to meet people.
