One of the very first rifles I ever built was a Hawken - and it was built from a blank, so didn't even have the 80% inlet or general shaping provided by a builders kit.
Now I will say something that may draw some criticism.
A Hawken is not are more "difficult" to built than anything else, all else being equal. The fitting of the lock, tang, pipes, butt plate etc etc are "procedures" that are the same regardless of the design.
So calling a Hawken (kit) advanced and a Barn gun beginner and maybe something else intermediate is a bit misleading.
Is a Hawken a little more "intricate" if you are trying to achieve something representative of an original - yes. But so is an early Lancaster if you are trying to get the carving correct.
For me "advanced" just isn't the correct term. Does having to spend more time, more care, more measuring, more subtle nuances equate to "advanced"??
So if your thinking "advanced" means you need an "extra level" of skill set, then I personally would say that is not the case.
I do agree after you have built a couple of rifles that are "less challenging" (plain stock, straight barrel perhaps, no carving etc) that the "confidence" you gain will make a more intricate rifle "easier" to build, because you won't be learning on the fly.
But if you can build a "beginner" rifle as your first, you can also build an "advanced" rifle as your first. Just in one case you might be using it for Bambi "this season", the other may have to wait until "next season".