I just saw a terrific summer quilt done by a quilting friend of mine. We live in Las Vegas, so we know all about the heat, and it's heating up early and plans to be a hot summer!
Anyway, I friend found a beautiful piece of fabric, multi-colored, in an African print, 54" wide and 6 yards long priced at $3 for the whole thing at an estate sale. She used my favorite summer batting, which is diaper material -- very thin and light, very breathable, but it adds body to the quilt. Then she backed it with natural muslin (double washed, as per protocol, to ensure complete shrinkage.) By using 3 yards of the African Print, she was able to put a top together that was about 53" (minus selvages) by 95" long. She is tall and likes the longer quilt, but the point is, the quilt could be made any length depending on how many yards you get. Then she spray basted and pinned it together, quilted around the shapes in the African print, put on a solid colored binding (which could be optional) out of fabric in her stash, and it really set off the blues and yellows in the African print. Ran it through a quick cold wash and tumble dry low. It's a perfect summer quilt, light as a feather, breathes extremely well (which two sheets sewn together might not, especially if they are a poly-cotton blend), and it both durable and beautiful. She said she did the whole thing in 3 days, working on it part of each day.
I know we really don't want to use "cheater's" fabrics, but there are alternatives out there that make beautiful tops without piecing, which makes it quick and easy. (Another friend of mine, for example, used an Indian Sari for her top, got it cheap off eBay.) The muslin and diaper fabric give it body without weight, and lots of breathability. The muslin came off a bolt in her stash. The diaper material is also cheap - but durable - and came from the
www.onlinefabricstore.com
Just an option to think about. If you're dying to do the sheet type, I'd hit all the thrift shops until I found a colored sheet top I liked. Then just baste them together, and use a simple overall quilt pattern. I like the idea of using contrasting thread. Binding is optional, but it can add color, and can be store bought cheaply, or made from your shash. And machine bind it -- don't bind the back by hand. Think: KISS - keep it simple and stupid. By "stupid" I only mean made by basic skills, not fancy ones, not that you have to be stupid about it.
Just my thoughts! Good luck with whatever you choose to do!