I am a lifetime Astros fan but do not think Bagwell is a HOFer. He was a very good slugger in an era of great sluggers -- Bonds, Sosa, McGwire. His numbers in general are impressive,there are plenty of players his age who have identical numbers that I don't consider HOF material, Frank Thomas, Jim Thome, Albert Belle, Juan Gonzalez and Gary Sheffield among them.
These guys are to the 1990s and 2000s as guys like Dave Parker and Jim Rice were to the 1970s and 1980s, great players, all-stars, but a step below HOF status.
Biggio on the other hand has made himself a HOFer in the last 3 seasons, averaging 99 runs per season from ages 37-39, missing only 22 games in that span and setting new HR career highs in the past 2 years. Assuming he stays healthy, Biggio will enter the stratosphere in several categories. Another 100 runs will put him tied for 16th with Ted Williams, 40 more doubles will put him 8th all-time. Plus there's no bigger gamer in the bigs.