To improve suspension...ride quality????

[Fried One]

I feel my car not handling the bumps so good anymore. I did replace all four shocks a few years ago. Lowered 1.5'' I installed a bump steer bushing. Replaced the end link bushings with polyurethane end link bushings. I also replaced the upper and lower rear control arms with a nice set from MAC. Other than replacing the shocks what else can I replace to improve my suspension. I also installed a strut tower brace and have welded in sub frame connectors. My car is getting up in age but it is still in very good condition with 187K on the clock. I kow my quad shocks need replacing but that does not effect ride quality right. It is more to control wheel hop.Any sugestions . Thanks.