One thing I'll say about hiking the route in France--you won't necessarily find a lot of English-speaking people there. I'm not sure how your French is, but if you have trouble calling ahead to make reservations (which is quite normal), I learned that the folks at the visitors centers in the middle of town can make the calls for you. They always spoke English and could help me with making reservations for finding lodging. They also have stamps for your credential. And a stamp in French is "tampon." Which still cracks me up. It's not often I can walk into a business and ask the cute girl at the desk for her tampon and not get slapped. =)
But I digress....
I consider the route more-or-less the same difficulty level as the
Camino Frances. If you can do the
Camino Frances, you can do the Le Puy route. There are parts that are more difficult than parts of the
Camino Frances, and there are parts that are easier than parts of the
Camino Frances. Start slow, take your time, and build up miles as you get stronger and can do more. But if you can do the
Camino Frances, you can do the Le Puy route.
I did my hike on the Le Puy route in August/September so I'm certainly not an authority on what kind of weather conditions you might face, but I've heard it does rain a lot in April. Some of the higher elevations might even get snow for all I know. But know there's a good chance that you might have a lot of rain at that time of year. Not something to cancel or postpone your trip for--just have the clothes and gear to handle it. =)
Lodging around Easter.... I have no idea how difficult it might be, but as long as you have a reservation ahead of time, it shouldn't be a concern. It never hurts to have a reservation!
I took a fast train from Paris to Lyon, then a slow one from Lyon to Le Puy. If there's a faster or better way of getting to Le Puy, I don't know what it is, but the train wasn't a bad experience. =) Le Puy is a pretty neat place to visit, though. If time permits, it wouldn't be a bad thing to dedicate a whole day just to enjoy the sights and get your bearings. =)
-- Ryan