I checked out your others at 100 pixels wide, and I think you're right: the dark against light drop shadow (or is that a glow?) just doesn't work as well. (Ironically, the one with the smaller type is actually easier to read at thumbnail size.)
The only thing I don't like about #5 is the gray font. Can you increase the saturation on that a touch? It also might need to be lighter after the saturation gets bumped.
I also might like #6 better if you put the font in the dark negative space rather than right across her chin. What about laying the title out more like you did in #5 -- with "love" shifted right rather than left? (Unfortunately, though, the font might be too small for a thumbnail, even if you did move the layout around.)
Camille
The only thing I don't like about #5 is the gray font. Can you increase the saturation on that a touch? It also might need to be lighter after the saturation gets bumped.
I also might like #6 better if you put the font in the dark negative space rather than right across her chin. What about laying the title out more like you did in #5 -- with "love" shifted right rather than left? (Unfortunately, though, the font might be too small for a thumbnail, even if you did move the layout around.)
Camille