Have you tried swapping the right and left speakers to confirm it's the speaker and not something else?
Nothing wrong with upgrading the speakers.
Polk 5.25s are commonly used front and rear.
Came across this on Ebay and didn't know where else to put it.
1:27 Harley edition TJ Rubicon.
https://www.ebay.com/itm/276357582316?mkcid=1&mkrid=711-53200-19255-0&siteid=0&campid=5337789113&customid=&toolid=10001&mkevt=1
My passenger side did that one time and I thought something was broke. Turns out the latch wasn't catching on one side. It fixed itself, guess it was just dirty.
I've played with the front CAs a few times, but probably not enough to say the vibes can't be dialed out. Newer TW driveshaft (balance rechecked by TW).
Just thinking that removing the MML should reduce the front angle.