There isn't much information on what you need as far as your plan is concerned. None of us want to pay more, but we want more so we end up paying for it. As far as price is concerned, you're going to find that all the carriers are very close in price for data, you'll also find that your long-time customer standing gets you the same benefits regardless of your carrier.
This business isn't any different than any other, I don't get discounts for being a 20+ year customer of my energy company, my mortgage company, my internet, or my grocery store. Why would a cellular carrier be any different? As a matter of fact, my cable company wants to charge me MORE for the same internet service the longer I am with them. I'm just happy all companies aren't like that!!