If you want to firm up your suspension, you can custom upgrade it to FE2. All you have to do is change the sway bars, add a strut tower bar and change the coil springs from another H body with FE2 installed. If you have the extra money to grab these parts from a junk yard, it really would be an opportune time to do it while you have most of the suspension torn apart.
Edit: To answer your question about those springs...those are basic OE as far as I know. They would most likely be as soft as the suspension you have now. But if you do the upgrade to FE2, just get the struts of your choice, I would recommend Monroe SensaTrac Sport and then new Strut Bearing Mounts and you will GREATLY improve handling.
Make sure to check your RPO tag in your trunk to see what suspension you already have. If you have FE2 already, then replacing your struts on all 4 corners should bring back that sport feel.