I'm not aware of any gals here (too bad, too!). Hopefully, if I'm wrong, none are offended!
The cost of some engines vs the cost of the car is an interesting issue. Here in the states, BDAs are probably mainly used for race cars, but many years ago, they made sense for Europas and Elans since the Kent block meant relatively few modifications were needed to make the swap. For me, it made sense historically since the BDA was sort of the next iteration of the TC. I understand the cost of building a BDA now is in the $20,000 neighborhood! That's getting close to the total cost of a nice Europa. As you found out, the TC is a similar if a little less expensive story. That makes a Zetec conversion a great option if you don't mind the non original aspect or the extra fabrication needed. I think you can get brand new Zetecs for a few thousand dollars!
I don't have any experience with the Renault Europas, but I expect their engines are probably less expensive to rebuild and I wonder if that is part of their popularity.