Oh, I do hope you go! I didn't walk the whole Arles route - I started (at the very end of April 2017) in Pau, and walked Lescar - Olorons Ste Marie - Somport - Jaca - Puenta de la Reine, and from there all along the main route to Santiago. It was a beautiful contrast to do both part of the Arles/ Aragonese route, and the
Camino Frances, as they are both very different. Arles/ Aragonese is very quiet (at that time of year, maximum 10 people a night), and you do need to book each night in advance, but beautiful, and there are some absolutely stunning places to stop - the monastery at Sarrance and the abandoned village of Ruesta were two particular highlights. Lots of communal meals and very peaceful, though even in May some hostels were not yet open.
I ended up walking with two retired couples from France, and because of one person's bad ankle and some terrible weather we took the highway for the day we crossed over Somport. Some of the trails before that were a little slanted and narrow, but I don't remember any truly hairy bits.
Feel free to ask any specific questions, which may help jolt my memories!