Just curious what seats others might have swapped in. My bench is so uncomfortable, but I don't want buckets. A fold down arm rest would be nice as well.

I would think an m-body or r-body with the fold down center might work.
like a new yorker or some other chrysler.
while technically they are buckets with a buddy seat, they kind of are a split bench.
you would have to find a 2 door to get a fold over for the convertible.