I love Hobbs 80/20 fusible quilt batt. You use a dry iron only on it. Steam or water will make it non-fusible. It is made to wash out after quilting. You do need a large surface to iron on. I put a sheet on the floor and prepare my sandwich. I iron the front first, flip it and iron the back. Then I re-iron the front if anything has moved. I put a few pins along the edge so I don't catch it while quilting. If you do a really big quilt, I re-iron the back after getting the center quilted.
As for a quilt pattern, if this is your first machine quilting go with a simple pattern that allows you to rest between spots. A loop de loop or star and loop. If you have some experience, I think something linear would look nice. Maybe a Greek key design in each card?

Maybe someone else will remember this video. The woman used the wall instead of the floor ( much easier on knees :) ) She pinned the backing to the wall and sprayed it. Then put the batting sprayed again and the then the top. It was an easy way to baste a quilt. Sorry I can't remember where I saw it.

How about with overlapping circles. On each block, maybe a circle over each card and one in the center of the block. Or, a row of overlapping circles, having 5 rows across in each 9-patch, then 1/2 way below so it halfway overlaps the row above, and so on? Clear as mud? wish I knew how to draw it into the puter to show you

It's beautiful

I see hearts.... a heart in each "card" and then more in between.

I had thought hearts and said no .... but now I'm thinking .... SITD for the cards with ♥s in the white space between.

I used fusible batting when I first started machine quilting with my home machine. It made it much easier to handle the twin sized quilts I was working on. Now I just use regular cotton and lots of safety pins. HATE spray baste stuff because it gets everything gunky. It's in the air, in your hair, up your nose, etc. Use it outside or in the garage on a large table.

I'd do something w/circles to sofen the squares

Beautiful quilt! If you decide to do FMQ, just stipple. Otherwise think about some sort of echo quilting in each square to bring out the geometric design.

Fusible batting is a waste of time. (IMHO) I had one come out good and never had success again. I forgot what brand I used the first time.

If you go for spray basting, I would recommend 505 spray. It's hard to find in stores, but you can order it online through Wal-mart and they deliver it to the store. That works for me!!

Good luck and happy quilting.

I've used fusible batting without a problem, but usually use it on smaller quilts. The batting won't adhere well if you have sizing in the fabric. For larger quilts I use the spray.