The difference between 4 and 6 ohms internal resistance would not by itself account for any difference in tonal balance you may perceive, comparing a 100R load on a XV-1S to a 1000R load on a TKR. If you're happy with 1000R, I'd say leave it alone. If you want to try 100R, the good news is that the latest iteration of the nude Vishay (aka Texas Instruments) resistors are a little more sturdy than were the older types, and 100R is not so low in value as to reduce the useable output of the TKR. They've added a kind of brace that links the two legs, so it is not quite so easy to pull the entire assembly apart, by accident. Knock yourself out.
Walker Signature Phono resistance
I am running the phono into an LFD NCSE and feeding it with a DV te Kaitora Rua on a WTAmadeus tt. I have SF Cremona M speakers. The cart load with the Walker is 1000k as recommended by Lloyd. DV however recommend 30 and TNT(from memory) advise good results with 300 into this cart. I am very happy with what is coming out music-wise but am wondering if it could be even better. I could just buy and try but the phono uses nude foil resistors and buying and shipping would be NZ$100 for a couple of pairs, so I'm after some advice first. Does anyone here have experience with either the cart or phono which would help me?