I'm not going to answer the poll, as those choices are more artistic ones that you should be making. Instead, I'll pass on what I've learned as I've started researching making my own fursuit.
The amount of fur you'll need for the paws is roughly 1/2 yard for the hand paws and 1 yard for the feet paws. It is better to buy more than you need, though, if you are new to working with faux fur and/or new to sewing. Having extra is also good in case you need to make repairs. So 2 yards would be a good amount to buy. Granted, these yardages are assuming that you are just going with one colour for the paws. If you're going with two colours, then you'll have to draw some diagrams and do some calculations to figure out how much of each you'll need before rounding up to the nearest half-yard (which is generally the smallest amount of faux fur you can buy).
You should decide for yourself whether or not you use all-white paws or paws with white and blue on them. If you are new to working with faux fur and/or sewing, however, I would recommend starting by making all-white paws first, as it is complicated enough. If you are really set on having paws with white and blue, then you can make them after you've learned from working on an all-white pair. And if you do chose to mix white and blue, you need to decide what that will look like.
You also need to decide how far up the arms and legs your paws will go. Will your hand paws end at the wrist or further up the arm? Will your feet paws end at the ankle like a shoe or will they go up further like a boot?
As for pile length--generally shorter pile faux fur is used on the paws, as that mimics the length of fur on animal paws. The two methods I know of to achieve that are to buy a longer pile faux fur and shave it down to the length you want or to start with a shorter pile faux fur. So you need to decide if you will be making more than paws and if you need colours to match. If you're going to make more of a fursuit in the future to go with these paws, then you'll probably want to buy somewhere between 2 inch to 3 inch pile in quantities large enough for all that you want to make (if finances allow) and then shave down what you use on the paws. Otherwise it would be easier to use a shorter pile faux fur.
Hope this helps!