If you are feeding, safflower is cheap, husk-less, and most birds love it. Squirrels won't touch it.
I buy Pennington Wild Bird (juncos, wrens, doves) and Ultra (nuts, etc. for cardinals and such). I also have a suet feeder in the tree. I don't mind the squirrels. I feed them whole peanuts and walnut pieces. There's one that comes up to me without hesitation. It's the crows that I don't like around. They're big, loud and greedy.
With the warmer weather coming this weekend, I'll let 'em fend for themselves for a few days. Don't wanna spoil 'em.