Having a good handling car is all about making small changes, the sum total of which make a big difference when combined.
Based on your description of things, I'm going to guess that you've never cycled through your full range of travel with strut rods with rubber bushings, strut rods with poly bushings, and adjustable strut rods. It makes a difference. I would also guess that you haven't seen how much the different strut rod bushings can affect the position of the lower control arm itself, because unless you shaved those poly strut rod bushings down it's really unlikely your LCA's ended up in the same place as they did from the factory. The factory used big soft bushings there for a reason, and it was because of the large tolerances these cars have. Having all the strut rods be the same length, with the amount of tolerance in the factory suspension, was possible because of the large, soft, rubber bushings. If you start taking away the large soft rubber bushings, you absolutely have to adjust for those factory tolerances.
The whole point of the adjustable strut rods is not to add caster. That might happen as a by product of them being adjusted correctly, but the entire point is to tune the length of the strut rod so that the LCA moves through it's entire range of travel with no binding at all. I've compared the movement of the LCA with rubber bushings vs poly bushings, with stock strut rods vs adjustable. And it absolutely makes a difference, there is a significant amount of binding that can be removed by tuning the length of the strut rods.
Now, does that make a car with rubber bushings everywhere unsafe? No, it doesn't. It doesn't make a car with poly bushings everywhere unsafe either, although in the case of the poly strut rod bushings you do really need to check to make sure that stuff ends up where it should be, because not all the poly strut rod bushings are the right size. You can see this post by @autoxcuda to understand that better. Cutting strut rod bushings for correct geometry?
And he runs adjustable strut rods now.
If you're happy with what you've got, that's fine. But not knowing what you're missing out on doesn't mean you're not missing out. There's no way I'd run my car with poly strut rod bushings and factory strut rods knowing what I know about how much binding there can be in the system with the factory strut rod length. And no doubt some cars are worse than others because of the loose factory tolerances. But that's kind of my whole point.
I dunno about all that, I've just done a ton of hands on work with my own cars and a fairly extensive list of aftermarket parts, lots of trial and error. Having looked into it though, the torsion bar suspension these cars came with is actually a great design. And it's capable of a lot, especially with a few upgrades.
But all suspension systems are a trade off, they all have pros/cons. And I can say after hammering my torsion bars out to change my oil pan gasket there are definitely advantages to not having torsion bars in the way! But it all depends on application, and coil overs probably still have a small advantage over torsion bars when it comes to tuning for track conditions. Not nearly as much as there used to be, with the much expanded availability of aftermarket parts for torsion bar suspensions nowadays. Both systems can definitely be tuned to a high level of performance, and at some point it comes down to what the person doing the tuning is more comfortable with.
