The MMDD was way too heavy and detailed, I thought, I walked from Geneva in 2012 and got to Le Puy after about 2 weeks. It is relatively easy to get lighter guides and information from local tourist information centres. I don't remember many (any?) donativo places...
Cost...? I am not extravagant, but I also like to have a coffee when I want one, and to have a glass (or two) of wine in the evening with food... so, I remember thinking that while 25-30 euros would be adequate in Spain, 40-50 euros a day would be nearer the mark in France.
I did meet a Polish guy who was walking (from Poland) with a fishing rod in his back pack, and on a budget of 5 euros a day, though!
It was my second Camino. I had walked from SJPP the previous year. Walking in France is physically tougher than in Spain. Very up and down! But the scenery is wonderful and some of the towns and villages are spectacular - Le Puy, Conques, Cahors...
Ahhhhh, I want to go back! Enjoy it!
Geraint