There are many options before replacing caps. Dampening materials, coating drivers with dope to make them stifffer, using dynamat (spelling) on the driver baskets and x-overs inside the cabs, and polyfil inside the cabs. Very inexpensive and worth while. Caps are caps, each has a benefit and each has a negative. 10uf caps can get up there in price and the sizes vary significantly. Mundorf oils are cha-ching $$$$$. The benefits to me are slight when compared to other options. Finding a better componemt that mates with your speakers is much more beneficial. For instance, try a preamp that is designed as direct heated or transformer coupled. I would be that the improvement realized with this would be five to ten times better then replacing caps. You should also take a listen to different speakers. Go hear the Nola Metros for example.
Happy Listening.