When I did my resume to get the job that I currently have (that was 3 years ago), my resume was mostly FIRST.
I haven't redone my resume since, but when I do, FIRST will be a much smaller part, so that it still fits on one page.
As for the size of Resumes, I have always heard that you make it one page unless you have 10 or 20 years experience and everything can't fit on a page.
The other important thing is to tailor your resume to the position you want. If you are applying for a job at FIRST, 2.5 pages of FIRST related stuff might be good
