Still try different strings. The string type makes a bigger different than the guage, the other bass with stainless steel has different strings, try the steels with the VFLs, I have had good punchy sound with blue steels on my foundation with VFLs. Different basses, different strings...
Rotosound has red silks at the ball ends too, ghs boomers have red silk but not on the ball ends for instance. I can't vouch for peavey strings, all my Peavey's were used, but one did come with red silks at both ends, stainless, I assumed they were rotos. It was a milestone II, so not usa