I like the idea of thinner blades, but you guys are right in that it's not exactly "totally" accurate to the OT. The saber blades in the OT actually varied greatly in their look because they were hand animated. Sometimes they were thick, sometimes they were thin, sometimes they were flat out FAT. There are specific shots and scenes where the blades are much thinner, and these specific shots have always been my personal favorite look for Lightsaber blades and I believe it is this look they are trying to recreate for rebels. Specific examples would be Vader's saber in '77 and certain shots/sequences in ESB. Vader's saber in ANH is pretty consistently quite thin and rather long. In ESB there are a number of shots, usually close-ups, in the final duel where either Luke's or Vader's (or sometimes both) saber blades are quite thin. I think several shots specifically in the carbon freezing chamber are like this.