It's the install on those tweeters that make them harsh. Ive been running a set of Polk MM6501s for the last five years. My first install was way to harsh for my taste and I eq'd it out like you. After I learned a few things, I figured out off axis in the sail panels on my car door were not the best place. There's lots of ways to smooth out the response. Might want to look into tweeter spheres.
As far as the blown woofer? I'm guessing its a woofer. I've been there too. Your amp is being pushed a little bit to hard or your crossovers are too low for the volume you want. Its a *****, I know. But there's a trade off between volume and digging deep with this speaker in my experience. Anyways, give Polk a call. If you fall under warranty you'll get a replacement. If you're like me and don't buy from dealers to save some coin, you can buy a new one, with warranty, for 80 bucks for just one woofer. It'd be a bit cheaper then replacing your whole system.
Ive heard good things about the JBL P660C. Comparable system but are supposed to be a little more relaxed with solid midbass response for a mid level component set. They actually look exactly like the Polk MM woofer with a different tweeter. The woofer has the same cone and dust cover design and maybe material too looks like. That ones just a guess though.