Is it practical to install stiffer shocks without also installing lowering springs?

[03Z33]

If you replace you shocks/struts with stiffer ones without increasing the spring rates, you may see a slight improvement in roll stiffness but the trade-off will be a much harsher ride and less control at the limit. You may look into some height adjustable coilovers which will allow you to run the car at stock height and you can also benefit from a stiffer front sway bar and adding a rear sway bar.