I want to upgrade my Turntable to something heavier

mahler, the short answer to your long question about balanced mode and hum is "yes". 

RB, I have never owned a Rega anything, but I do believe that the diligent end user could wire a cartridge in balanced mode even using a Rega TT and tonearm, once you know where the connection is between the tonearm or table ground and cartridge ground. Then sever it. You could ground the tonearm or TT separately, if necessary, once that is done. I did not mention it because I did not want to confuse the OP, but there ARE cartridges that cannot be wired in balanced mode, because they use a single common ground for both channels.  That goes for at least older Decca and Grado cartridges, maybe others.

Using "balanced cables" in the absence of balanced electronics does nothing except exhibit any differences between the cables themselves and whatever else you have been using in terms of SQ. But there are none of the noise benefits associated with balanced operation. Like I said before, you can have perfectly OK performance from a single-ended system with no annoying noise issues, too. And single-ended electronics tend to cost less than true balanced electronics, because of lower parts count, or at least they can be manufactured for lower cost.

@lewm 

The OP has a PS Audio integrated amplifier which accepts one balanced input, but at a price point that suggests the amplifier is not fully balanced internally.  From my brief reading of the specifications, the first version handles Moving Magnet cartridges while the Mk 2 version also accepts Moving Coil.

All other things being equal, I would use balanced cables from the deck because there is nothing to lose, and more immunity from EMI directly affecting the cable.  I note that balanced cables can be terminated in RCA connectors as well as XLR, provided the RCA connections are not grounded. 

If I were running a Moving Coil cartridge from my Holbo, I would use cables with RCA connectors at one end and XLR at the other. I know the Holbo RCA connectors are not grounded, because they support the powered DS Audio optical cartridge range.

I have an XLR balanced cable for my SME tonearm which will provide a straight run from the cartridge to the phone stage, when I get around to installing it.  Oddly, with my current Moving Magnet cartridges and SoulNote phono stage, the balanced cable will work but only in single-ended mode!

You can probably answer this question for me.  When balanced cables are used as interconnects, the effective signal voltage is twice as high as a single ended cable.  I suspect there is no such advantage with cartridges.  Am I right?

As you imply, at this price point most home users are very satisfied with the sound quality they get without bothering about balanced anything.

Tend to agree with the above my perferance is wall mount for the stated reasons however I live in a mining town withusually scheduled "earthquakes" and large truckes transiting. Currently the table is on a heavy dresser which seems to reduce the sprung floor trampoline effect from children - still requires care and descretion ...

Re balanced - personally think your going down a "rabbit hole" noted you have an excellent amp. Suggest spend time investing in a high quality phono stage for example I use a Dynavector in Dr T mode which is excellent. Also re the table suggest if you need to change look for one open to step by stepupgrading allowibg tweaking and fiddling. Regas and Linns are good for this. Also if you have tge urge have you thought about buying a kit or build your own? This can be entriguing and interesting and through it you learn a lot hands on about audio gear?

RB, Yes you can use RCA connections in a balanced system, but not only must the ground side of the cable not be grounded, it also has to be carrying the negative phase of a balanced signal. (Obviously, if the signal is SE and the ground end of the RCA is not grounded, you would have horrendous loud hum, anyway.) The disadvantage of using an RCA for balanced, if all else is correct, is that many RCA cables use a conductor for the ground side that is not as good as the conductor for the hot side and may even be the shield itself.  So, if one is going to use RCA for balanced, I would make sure the ground conductor is separate and equal to the hot conductor and not synonymous with the shield.  You don’t get any benefit in terms of gain from using a balanced cable with XLR termination unless both ends of the cable are hooked to balanced devices.  That Raven linestage referenced earlier is very unique.  I looked at the schematic, and it seems they take a single-ended input and produce a balanced signal internally with their input transformer, 1:1, so no gain from that transformer but just creates a balanced signal internally.  Then they amplify the signal in balanced mode, and at the output they use another transformer to both convert the signal back to SE and reduce output Z, converting signal voltage to current. Very simple but elegant. Would that device give you a bonus for gain in balanced mode? I dunno. The gain benefit of balanced operation is linked to driving a balnced device with a balanced input. 

My Boulder integrated does not have RCA inputs. I have absolutely no issues using XLR cables in that connection. I realize that neither one of my two phono stages, one tubed and one solid state, is a true balanced design. In a system where both RCA and XLR connections are possible, the selection of phono stages is much wider than it is in my case. You can explore less costly options.