I'm a big fan of the Valk. Without any research or anything, I grabbed one as my first disc. I just saw "Distance Driver" and grabbed it. I lost my 171 DX and replaced it with a 175 DX. This disc tells me when I screw up but it rewards me when I nail it just right. I'm trying my best to like my Roc and it's slowly coming around, but I find myself grabbing the Buzzz more often. I'm also loving the T-Bird.
My first putter was a 150 Aviar and I really like it, just not fond of the light weight. I picked up a 175 Magnet and love the thing! As soon as I can I'm grabbing a 175 Aviar.
Not a bag suggestion, but make use of the technique tips offered on here. In every thread, there's something you can take with you that will make a small improvement in each aspect of your game.
The most important for me have been...viewtopic.php?f=2&t=9959
Which is explained very well in the video on page two of...viewtopic.php?f=2&t=11614&start=15