I think
Glynis has a heroic, medieval feel, which is cool.
Glenda on its own would sound icky and dated, but next to
Glynis it is given a similar association.
Penelope matches the imagery (
Homer!), but not
Muriel, which I find too old-lady. Others may disagree.
I prefer
Glynis Penelope to
Glenda Penelope, because of the repeated en that others have mentioned.
A few combos:
Glenda KatrinaGlenda YsabelGlenda DanielleGlenda RolandeGlenda WilleminaGlenda IvonaGlenda Dominique