It's absolutely ridiculous to select someone other than Kristin Chenoweth as the ultimate Glinda. Here's why.
Glinda was written for Kristin. The jokes Glinda makes were tailored to Kristin. Anybody who follows her is merely emulating her - because originally, Glinda WAS Kristin.
My point is:
It's fair to prefer other performers, to like other performers other than Kristin and not to like Kristin that much.
However, it's absurd to say that Jennifer, Kendra, Kate or Megan is a better GLINDA. Maybe you like them better as performers, but they are not better GLINDAs.
You simply like them more than you like Kristin as performers. Kristin IS Glinda. Not because she's the best performer, but because she crafted the role. The role is what it is because she originated it.
If somebody else had originated the role (say, Jennifer, Kendra, Kate or Megan), the role would not be the same. It would not be the Glinda you know. EVERYTHING, right down to the wording of the jokes and the vocal melody lines, would be utterly different.
The role is Kristin Chenoweth.
I hope to God I explained it clearly.
-The Color of Flame
"I am the sound of distant thunder, the color of flame."
CARRIE the Musical