The trick with pallettes isn't to 'just' do bog standard ramps... that's to say, selecting the brightest color, then darkest color and doing a 'ramped' gradient scale between.
Without risking an application war, it does depend on what app you're currently using to do your pixels. That asides... the key to interesting pallettes is to hue shift each color along the ramped scale...
so, for instance, If you begin with your scale you're currently using... take the darkest shade and using the RGB sliders (in whatever app your using) and add a touch of blue...
Now, take the brightest color in your scale and add a touch of Red.
Now go to the mid shade and add a touch of green...
So you should have 3 color tints in your scale?
Now... 'just' ramp between each of those 3 indexed colors... et voila... a more interesting pallette...
I'm just showing you a method here, there's more ways to work the pallettes obviously... but this way is a quick way to add interest to bog standard ramps...
Once you get a grip with that method, you can go in and tweak each color independantly... using a better understanding of color tints and ramps.
One final point... once you have that interesting ramp... you can now hue shift the whole lot... making for further interesting pallettes...
Within reason obviously...
