I guess this all boils down to type of batting also, and whether or not you pre-wash your batting? Given the cost of it, I'm afraid to try it! lol
I prefer the flat look because, first of all, as you stated, it shows that everything has been pre-washed and the recipient will have no worries about future laundering. I think "flat" is a cleaner look. BUT...I like the crinkled look for certain items, especially if I want them to look "aged"! lol
One of my GD's has requested a quilt in, as she puts it, "old time" fabrics (in shades of pink and hot pink)! She actually gave me a blouse she's no longer wearing to show me what she wants, and it's a very tiny calico print! lol So, I won't worry about pre-washing batting on this one as I'll want it to crinkle. I'd NEVER have guessed that she would want a good old fashioned looking quilt!
She's a very popular young lady, cheerleader, loves makeup, hair, fingernails, etc, and is not yet 15, but will have completed her graduation requirements by the end of this school year!!! Yeah, proud grandma moment. lol