1)
What is the significance of "Lifnei Shever Yigbah Lev Ish"?
1.
Malbim: It already taught "To'avas Hashem Kol Gevah Lev Yad l'Yad Lo Yinakeh" (16:5). I.e. Hashem will punish him immediately. Haughtiness of heart is a sign of breakage to come. An Ashir who considers his wealth to be a tall wall (11), he will be broken.
2)
Why does it say "v'Lifnei Chavod Anavah"?
1.
R. Yonah: This is like it says "u'Shfal Ru'ach Yismoch Kavod" (29:23).
2.
Malbim: The humble person, who takes refuge in the strong tower of the name of Hashem, Who dwells with the crushed and low-spirited, he will merit honor.