One thing on the 6.5x47L side is a little more barrel life than the others, especially the 6.5x284.
This might be a unthought of factor in a rifle for someone starting out. Once you get that rifle built you're going to need to figure things out that no amount of forum reading or good advice are going to give you. You're going to need to shoot it, screw with something, shoot it some more, figure out "is it me or the setup", shoot it some more, experiment with X, Z and G, shoot it some more. Having a nice long barrel life cartridge is more conducive to this than a burner.