You wrote
I'm a little nervous about it, so please give me any suggestions you may think of to improve the reality of the situation.
I think I can help
Let Brian or Clark save Lois from becoming bug splat or as Pam calls it 'sidewalk pizza'
Seriously, I'm not sure how you can improve on great writing. Luthor has to be a little 'overzealous' and thus, overwritten to get Lois and Clark to the balcony. His desire to 'marry' Lois as a way of possessing her, and keeping Clark alive as way of controlling her, makes sense.
Henderson coming into save the day also works.
So, only improvement I can see is to end it with Brian saving them (which means that Clark doesn't have to reveal himself) or Clark saving them and hiding the revelation.
Up to you...
And have fun baby-sitting
gerry