That's why Toyota builds sooooo many good sports cars these days, all that time spent from the 60's up until they killed the Celica/MR-S in 2005, they've really refined the recipe for a great sports car. Oh wait...
Just kidding man, I know the business doesn't make sense for a sports car anymore, but you'd think by now they would be able to build some amazingly capable cars. Now, about that legislation on that sort of thing...
You know, I haven't owned a Mk4 (yet, would have by now if I didn't have my heart set on building a badass Mk3), but if I already had one, I would probably look at bringing a little variety into my life. Much as I love the idea of a Mk4 for myself, the old lady wants one, I'll let her buy one of those, I'll probably get an NSX for myself. Variety... spice of life my friend.
Not saying a Mk3 is a step backward (they're really nice cars, especially if you can find a relatively stock one, or one kept in stock condition), don't get me wrong.