Good luck to you and your friend, Profannie. I'm in a similar situation with my best friend from high school having a lumpectomy followed by the targeted radiation. Unfortunately we are a thousand or so miles apart and have to send her a quilt to give her the hugs I can't.
I've been having issues because I'm a planner, not a rapid response quilter! But this is what I know, it is more important for me to get this to her quickly than it be perfect. There will be plenty of time for us for me to make another quilt for her. She is going to know and recognize what this gift means and it means love.
Hang in there.
As for the design decisions -- I don't really know what "rustic" is. I can make some guesses, but I'd need more to go on. I recently got excited by a very fast and easy design called Simplish, here's where I first saw it:
2019 Fabric Moratorium
I think I could make it rustic style by a fabric that looks like peeling paint/fence boards and strips of colors stacked in the rectangles similar to the first pastel top, and then a coordinating fussy cut fabric in the squares.
Here's my first Simplish, I added a border and some other stuff...
Virtual Quilting Weekend--July 26-28, 2019
And here's an official tutorial on it:
https://www.shabbyfabrics.com/Assets...orDownload.pdf