Jolida 502B Integrated amp or Schiit Freya + with Vidar amp?

Hello, I currently have the Jolida and was wondering if the Freya +/Vidar combo would be a significant improvement?  I currently have Merlin TSM-MM speakers and an Epik Legend subwoofer.

I was also wondering if I would notice a bigger difference by replacing the Epik Legend with a Rythmik F12G subwoofer rather than going to separates?

I cannot afford to do both at this time.

I would appreciate your help.  Thanks in advance.