So I’ve been wanting to change out some parts on my 2019 RG470 and I could use some advice for any retrofitting or replacing components.

Okay? You'll need to actually provide details of what you're interested in doing.

Here is one sugestion.

https://www.dimarzio.com/pickups/wir...sh-split-coils

I’d like to upgrade the Edge trem to an actual Floyd Rose, some chrome hardware, and a new bridge pickup. I was thinking a Pariah Pasadena series black, or a Seymour Duncan ‘78 model or Frankenstein.

My biggest concern I guess would be which Floyd would fit properly in the stock routing.

I guess my biggest concern would be the Floyd, and which one would fit with which locking nut, and matching the radiuses.

Pickups will be fine. F or trem spaced will aesthetically line up the pole pieces with the strings, but standard spacing will still work. The Frankenstein is regular spaced, but you can get it as the IM1 from Seymour Duncan's Custom Shop. They'll do Trem spaced if you ask. Both are awesome sounding pickups. Had both, and still retain my Custom Shop IM1 with a couple little tweaks.

Gotoh Floyd Rose is probably the best bang for buck licenced Floyd Rose, with improvements over the OFR. I'm guessing that it should replace the STD-DL that's on your RG. You may need to do a little sanding routing to fit. Someone else may be able to confirm.

Will the Gotoh locking nut replace the original Ibanez? I’ve heard some guys say that it’s good to leave the stock nut but I’m not too sure.

If you intend to replace the nut, you need to have the correct radius, width and mounting specs. That particular RG470 has a Wizard neck that's been on the mid level guitars for some time, so 43mm wide at the nut and a 15"/16" fingerboard radius. The Gotoh GHL nut fits this spec. The current version of the guitar has a top mounted nut, don't know whether that was the case a few years ago. Either way, you can get a rear or top mounted variant from Gotoh.

On the other hand, if the stock nut works as it should, probably don't need to change it.

Another thing to consider if you plan to get a Gotoh Floyd is that some modification may be required to use the Gotoh inserts/studs. The Lo-TRS type inserts are hollow, while Gotoh ones are solid because the studs have the locking set screw in them, and the dimensions are, I think, different, so some drilling may be required. With an Original Floyd, this is is necessary to use the replacement inserts/studs. On the other hand, you can keep the stock TRS inserts/studs, see here: https://www.jemsite.com/forums/f21/gotoh-rf-50577.html.

Of course, make sure that the block length is appropriate too.