My favorite is Scrappy Crossing from Annie's E-pattern central.

I agree with copycat...the Take 5 is my go to for quick and easy in any size.

HST's are my go to for most quilts that are traditional. The depression block is good for some of my ever growing piles of scraps.

D9P is the most versatile for a variety of looks from a simple and easy pattern. Some of these I have never tried but think I will be adding them to my list!

Warm Wishes is my go-to pattern. It is very versatile, I've used it for baby, sports, nature, masculine and school color quilts

when using 2 layer cakes, what is the final quilt size?

I like generating large HST's, often as leaders/enders, keeping them in a basket and then designing with them up on the design wall. To make HST's, I always make them with HST papers I print myself using the "Triangulations" DVD. You can choose your HST size, print the papers and sew away...fastest and most accurate way to do HST units which can be frustratingly slow and hard to keep accurate via the usual methods.

Not my quilt, below (which is from the book "Patchwork Essentials" by Jeni Baker), and my triangles are smaller, but you get the idea! There are tons of ways to arrange HST's into great quilts!

Here is another type setting for your favorite fast quilt, AZ Jane. It makes a fast child's quilt.

Yellow Brick Road, Take 5 and Rail Fence. When I need a quick quilt, I pick one of those.

Disappearing 9 patch. Looks like way more work that it is.