I love all the fabrics you have used in this quilt and the panel on the back is lovely! With regards to pens for the label, I have just completed my first label and hunted high and low for a fabric pen that would not wash out. The pens I tested were a black Laundry Sharpie, a black laundry marking pen (looks exactly like a ball point pen) and standard gel pens (not fabric pens) in purple, red and gold and this is what I did in my test:
I wrote two messages for each pen, one I ironed and one I did not.
I washed the test fabric with normal detergent
The first wash was gentle, scrunching the fabric in my hands, similar to a washing machine
The second wash, I went all out and rubbed the fabric together really hard to purposefully try and remove the ink
My results:
The Laundry Sharpie bled while I was writing on the fabric and looked awful but it didn't wash out no matter how hard I tried.
The ball point Laundry Marking pen wrote beautifully. The non-ironed test washed out with mild rubbing. The ironed test faded with mild rubbing.
THE WINNER! The gel pens, surprisingly. The non-ironed test stood up to mild wash but faded dramatically with harsh rubbing. The ironed test stood its ground with no bleeding, no running and no fading, even with harsh rubbing. All the colours stayed bright and crisp. (The gel pens are from Staples).
Unfortunately, I am useless at naming quilts, so cannot help you in that department!
Good luck, I'm sure you will come up with a beautifully appropriate name for your gorgeous quilt.