Spitting Yarn

I knitted on blindly with DB’s hat, but the nagging dissatisfaction I had with my cast on grew and grew.  My DB and the yarn are so lovely!  They deserve better than this(!)  The hat has been frogged, but not before I took a photo for forensic purposes.  Look:

The picture is rubbish because I took it in a hurry before leaving for work, but hopefully you can see the ooky cast on.  Ignore the odd ribbing (I ktbl on the first knit stitch after a purl section to avoid the gaping I usually get between purl and knit stitches in ribbing).  Can you see that the first row of the knitted rib panels looks holey and crappy?

The cast on is knitted, because I tend to cast on quite loosely.  If I use the long tail method, the cast on looks twice as bad.  Is this simply a question of looseness?  Do I just need to go down a needle size or two for my cast on?  If anyone has experienced a problem like this and solved it, or has any idea how to avoid it, I’d be grateful to hear your thoughts. 

Also, does anyone know of a solution to the looseness I get in ribbing in the transition between purl and knit stitches, other than knitting throught the back loop or pulling hard on the yarn (which is uncomfortable and doesn’t work for me)?

Problems, problems.