Looking to maybe replace seat foam, seems to be original although previous owner had two bottom leather panels replaced . I am going to paint/dye them to better match. Think it will make much difference in feel? Thanks for input!

If a couple of the seat covers have been replaced I would think that the foam would have been replaced as part of the project - at least that is what I would have done.  I have never dyed leather, or anything else for that matter, so no help there as to what the feel of the leather is like afterwards.