Sewing clothes without a pattern

I like designing clothes, and I'm a passable seamstress, so occasionally I whip up a little dress or jacket that strikes my fancy. After years using an old industrial Kenmore with only one stitch (I made my wedding dress on that thing!) my husband surprised me at graduation with a new machine. Sadly, the gift coincided with the cessation of Wal-mart's fabric department. Luckily, it looks like my favorite dollar-a-yard source is back and I recently bought some fabric that toes the fine line between cute and frumpy.

Is it "aw" or "maw maw"?

I only had 1.3 yards of 45" fabric, so I knew I had to make a simple dress, but with a floral pattern you have to be careful not to make a housedress or mumu.
When I design and sew without a pattern, first I sketch the finished dress, and usually I also sketch out what particular pattern pieces will look like.

This time I decided on a simple one-shoulder dress with an oriental look. I put in an elastic waist to create shape since I planned on having a blousy, gathered top and skirt. I tapered the hem of the skirt to add more structure.
Once I make a design, I free-hand draw a pattern on the fabric with pencil. Sometimes I trace other pieces of clothes - for example, if I want to make a short sleeve, I might use another short sleeve top to get the armhole and sleeve right. You can also use a measuring tape and body measurements, of course.
Don't forget to add seam allowance! I also leave extra fabric if I'm unsure how something will hang or fit - I did that with the neckline on this dress since I have not sewn a one-shoulder dress before.
Before doing any sewing, I try the clothes on pinned together and make adjustments.

Try it on with the shoes you would wear it with.

Then once stitched, I do a try-on and take a picture. I study the picture to look for flaws. You can see that the side hem is messed up on the skirt one side here - my tension was too tight and it looks wavy from very slight puckering. These things are hard to miss in a mirror, which is why I take a picture.

When I fixed the skirt hem I also made it a little less full.

 The finished product got lots of  compliments! The loose fit on the top made this dress ideal for walking outside in the August heat, so I wore it for Dirty Linen Night. The only problem is that I had to skip the pockets I had planned to put in the skirt - there just wasn't enough fabric leftover!

If you were choosing a cocktail-style dress that had to be the last one you ever bought, would you choose basic black off the rack or a completely unique brightly colored frock designed just for you?