I have personally played with a 9 agi build and with a faster weapon than the flamberge (nodachi). It was still too slow. Go for 12 agi at least, maybe 15. Also 0 IF on a str build is bad, you will get hit because you're so slow, str characters need hp and good armor to do well.
Xant he doesn't want a balanced character, but a str one. Balanced is a different category, as would an agi stacker be.