QuSince you decided to offset the columns, maybe every other column should have 2" cut off the first block. That way every other column will definitely 'not' line up and look cute.
I've been quilting since 1992 and my sister and I took classes together to learn to quilt. You might try a beginner's class. Usually you make 12 blocks, all different, and learn all the tricks of the trade.
Also, chain piecing is taking two pieces of fabric, right sides together (RST) and running them thru the sewing machine again and again (since you are just using squares of fabric for your blocks) and then taking the two pieces just sewn together and attaching them to another two pair and running them thru the sewing machine again and again until you've sewn all the blocks together. Then sew the four blocks to another set of four blocks and run it again and again. It cuts down on time. I'm probably not explaining it correctly but look up chain piecing in quilting and it'll tell you how to do it. It cuts down on your sewing time by about half. It's a good trick to know.
Good luck. I gave away a kit that had Minky in it because I knew it'd roll when I sewed with it. I never thought about using a Serger. You had the right idea regarding that, but a 1/4" seam is sooooo important in quilting. What's more important tho, is that all your seams are the same width exactly. Not a hair off. It's something we strive for. It's number one for achieving a nice quilt. If you continue to quilt, figure out where 1/4" is on the bed of your machine and use something to mark it. I buy Seam Guides from Guidelines 4 Quilting to mark my 1/4" mark. I also use a thing called the 'Prep-Tool' to achieve the 'scant' 1/4" seam. You can buy it from Guidelines 4 Quilting, also. If you bought both these items, you'd be set for a scant 1/4" seam.
I figure you will start quilting since you are so earnest in making this first quilt. I bet it is your new hobby! We have lots of tricks to quilting and if you read this board and ask questions first, you will be off and running in no time. You can Google 'How to quilt' or look it up on YouTube. YouTube is great for learning to quilt. Jenny Doan has a few hundred videos on quilting and different quilts. You should check her out. She has a video on 'birthng' a quilt that would be great for this first quilt. Please check it out. It will save you so much time and you will enjoy it so much.
Good luck and welcome to The Quilting Board. Keep coming back. You'll be a pro in no time!