i think you will probably succeed in deferring this offer as it was said in the email that the graduate program director will normally approve the deferral.
From the letter, it seems that it is you that request defer of admission.
I think this letter mean that you will get admission next year, but whether you will get financial support is unclear.
"automatically considered full financial aid" only means you would don't have a seperate application for full financial aid, not means you would get full financial aid aumomatically if you are admitted.