A priori you don't have a true/real problem to " better match with the Kleos " because you already have a good match.
""" It’s not that I am not getting decent volume however I do have to turn up the volume quite a bit in reference to my other sources ...""
the other sources are different, for me makes no sense try to even the different sources levels especially when we are talking of cartridges.
A SUT means adding transformers ( " many meters of wires. ), input connectors, cables and output connectors where at each one the Kleos great and sensible signal suffer a true degradation losting recorded music information that you can't recovery at any place: the cartridge signal has to pass trhough to all those additional links. The heavy degradation is for ever. Why do you want to do that?, makes sense to you?
From my point of view the PH-7 is no problem with the Kleos. If you want to spend those 3k-6K maybe could be better making the VPI Prime upgrades offered by VPI and maybe too you can get better quality improving the IC cables between the AR and 2600 and/or between the VPI tonearm and the AR.
You have " land " to improve your analog quality level performance other than what you are thinking to do.
Well that's me, only an opinion.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.