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That seems perfectly fair, and I think it's an excellent plan. The more Stacey-flirting, the better, I say...

No.... there must always be a differentiation between quantity and quality. MORE flirting does not necessarily equate to BETTER flirting, in other words.
For example, saying "Yay! Stacey smiled!" is not necessarily good flirting, because it implies a dissatisfaction with recent smiling occurrences or lack thereof. You might as well say, "Hey, it's nice to see you smile again, you sourpuss." Although the "It's like the sun came out" part is pretty good, I have to admit.

On the other hand, the way I would have done it would be something like, "look how Stacey's smile lights up even the dimmest threads".
That's neither overt flirting, nor is it condescending. It's subtle. It's good and to the point without being over the  top.

As a guy who has been appreciating women for a good while now, I have to say one of the things I've learned is they tend to be pretty smart creatures. Probably smarter than men. And therefore, they easily see through the simplistic and overt flirting. I think they probably more appreciate those who try harder with it. ;-)

Nice to see you smile. Jeez, you might as well say, "Hey, your hair looks great". They already know that stuff, man, you gotta come up with a more original angle. ;-)