I like Electric Quilt but it is a little expensive - at least to me it is. There are some other free options out there though. 1.
Jenny Beyer 2.
Free Quilt Patterns 3.
Quilt Study 4.
My Web Quilter 5.
Quilting Studio 6.
Quilt Assistant 7.
Thread Bias 8.
Quiltivate 9.
Pattern Jam
I have all these bookmarked and have try playing with 6 of these so far. All have a learning curve but so would Electric Quilt.
I haven't made all that many quilts and those I have made, I have started with a quilt I liked and then used graph paper and drew out what I liked about and then what I wanted different and they have all turned out just fine and just the way I wanted but my tastes aren't along the traditional line. But you can design whatever on all the above. They all have programs that are completely free and some want you to upgrade to bigger and better but I've not upgrade any. Just trying to give you a starting point for zero money.