Expedites really have to be done at each stage, but also generally only if you're preparing for deployment, i.e. have orders and all for it. There isn't technically just a military/veteran expedite, even though each case is unique, generally would need to be some outstanding out factor(s) in play for it.
As for the I-134. Just send what you have. Current income is main thing. Send 3 months worth of LES's (6 of them, unless you chose once a month payments), and can include whatever tax transcripts/W2's you have. Current income is main thing they care about really. If you don't have a large savings, no need really for banking statements. And everyone has some debt generally speaking (rent, car payments, mortgage, and student loans), don't over think it honestly.