Just another thought for OP.
What I find most with women and cars is for the vast majority its more about what they look like than anything else. So if you could do fine with one car then the better daily seems more logical.
What you need to find is the one where she likes the car more than she doesn't want the performance, if the issue with the performance is the not feeling comfortable with it then what can you do to limit that effect.
Maybe an auto, they tend to be easier to drive than manuals in faster cars.
Then the angle of what it looks like etc. If you can think of some that you think might get a balance acceptable to you then you can work on her, for example I find women like minis, and TTs
So something like a JCW mini, or a TT to test drive?
You could try the GT86 angle like mentioned although suspect the fact she doesn't want a car thats fast is really she wants one that feels safe and they dont really meet that criteria.
The new MX5 would be a good bet, but too expensive I would guess at the mo.
Partly comes down to really what you are after, speed, looks, rarity etc