I agree with involving the new DIL in the selection. The only thing I would suggest is you have a few quilt pictures/patterns for her to pick from. If that goes well, Lunch and a trip to the fabric store.
My MIL would make baby quilts for the grandchildren and great grandchildren. They were printed cross stitch. She would have the expecting mom pick out the pattern, she would order it, work on it and present it at the shower. One of the mom's picked a twin size and every inch was cross stitched. It took the MIL until the kid's 1st birthday to get it finished instead of the normal 3 months for the baby blanket size. The MIL did it, but it took the enjoyment out of it for her. Just watching how all that unfolded taught me, you pick what to choose from.