Hey Hairtwin!!
First of all, I must say that your hair is freakin' GOURGEOUS!!!! Have I been under a rock????
Okay with that said, here is my advise on the matter.....If you recall, last year, I cut my hair above shoulder length to GET RID OF the layers. Now I have nice even hair all one length....yada yada...and guess what?? I'm thinking about the freakin' layers again. But this is what it comes down to: you'll end up seeing someone with those nice full fat ends and you'll wish you had it all one lngeth again (like I did)....then you'll see someone with a beautiful layered style, and you'll desire the layers.
I would say keep it all one length if your desire is to have a nice pin curl set. I think if you use the right product you should be able to maintain the look you want. Now, I don't necesarily know what that product is....but I know it exists 'cuz other people have all one length and have nice pin curl sets. Ultimately it's up to you. If you feel really passionate about it, then go fo it! You can always grow the layers out if you so desire. If you do decide to cut, I would not do dramatic layers.....just subtle enough to give you "that" effect.
Good luck girly!