How is Henin inferior to Venus?
Far superior in weeks at #1, same number of majors, won 3 out of 4 instead of 2 out of 4. Venus only made 1 final at AO and FO each. Henin made 2 finals in the major she didn't win and took a set in both (hell was serving for the match against Mauresmo)
What is most important is that Venus hasn't made a major final outside of SW19 since 2003. Once she passed her peak, she was incapable of even being a factor outside of grass. Compare that to Henin who straight after her comeback managed to make finals at AO and took a set from Serena.
Then there is the fact that she dominated a year completely (2007) Venus has never dominated a year to such an extent.
Finally, Henin also did that in much less time.
The only thing Venus has over her is number of majors finals. Without only 1 final each at AO and FO and 11 weeks at the top, no way she is better than Henin.