I have a MIJ '75 RI from around 2003. It does have the incorrect pickup spacing (60s style) but as you commented you lean towards a more vintage tone, I would say that it isn't a bad thing necessarily. Still, the woods chosen (heavy ash body) and the somewhat thicker '70s style U-shaped neck (which is in fact very much in keeping with the originals) add to the proper '70s vibe and tone. The weight on the '70s ash models is always a consideration, as the originals can be quite heavy too
I would like to add that the Japanese JB75US models don't require a pickup upgrade at all, as they're fitted stock with American-made vintage reissue pickups which sound excellent. The pots can be a different story, and it's often worth upgrading those to something with a smoother curve.
I modded mine with a Hipshot Xtender (and changed the other tuners to the same model Hipshot for the hell of it and to match the shine, as the original Gotohs had much more patina), a Badass II and at first I had an Audere JZ3T preamp in it but I didn't like it so switched back to passive but with a 6dB bass boost under a rotary switch to match the appearance of the other knobs. I had the jack moved to the side of the body, and had a battery box routed in the back. I kept the stock pickups, as they're excellent.
Here it is before the preamp was added: