93Blu, you´re right about the scort´s handling. Even the LX in its stock form takes curves very well, and has potential to be tightened up even more.
As for crashworthiness, ANY car has a lot more strength and rigidity in the passenger compartment, because that is engineered in for safety. The front of any car forward of the firewall is considered a ´crumple zone´ meaning it´s designed to be deformed during a severe collision saving the vehicle occupants from injury or death.
In terms of its engineering, I would highly doubt that any Hyundai is superior to an Escort. Ford and Mazda, who jointly developed the 2g scort, have way more experience than upstart Hyundai. In my opinion, Hyundai´s are (mostly) nicely-styled, cheap cars. Sure, they have potential to be improved with some mods, but so do all cars. The Escort is just a better platform to begin with I think.
Given all the time and energy you´ve already put into your 1.9L engine, I´d look for another scort to drop it into. They go for pretty cheap, especially if they need an engine or major mechanical work. Think of all the good times your scort has given you! Why would you want to throw that all away by going to another platform, which you would be completely unfamiliar with? Go with what you know, I say!
Hope this helps!