One suggestion I'd have that is really cheap (sorry?), but works...
Start by replacing some of the stock swaybar bushings with eurethane. I have gone this route for years, with cars and trucks. For getting a better response without a stiffer feel, replace just the inner strap bushings. To get an effective higher bar rate, replace the straps and the end link rubber with eurethane.
I did this on my old 4 runner with great success, and on dozens of cars, race and street. Most times you can use an off the shelf strap (the kind with the zerk fitting is the best IMO), 27 and 25mm are standard parts for suspension techniques. The multilink bushings might be tougher, but a lot of 'merican iron can interchange (I used some sort of chebby app for my 4R).
Scott Justusson