I agree with pretty much everything you said in your review; the choice of tracks used from Lufia 1 could have been a bit better. It might be worth noting that Curse doesn't use "Peace of Mind" from the original Lufia 2, but replaces it with the Priphea Flowers theme from the oriignal (although, for some reason, an arrangement of "Peace of Mind" and the first two battle themes from Lufia 1 are both in the ROM, despite not being used in the game).

Some (maybe most?) of the samples (like the guitar and harp) for Neverland's DS games came from the Roland SC-88, but they're sampled instruments, just like the original Lufia 2, whereas Radiant Historia's music is streamed, which is unfortunate for the former. I would have been happy with either of the options you presented for a better arrangement (an orchestral version better than one using the "sampled originals", of course, but either being a good choice). If it's of interest, Noriyuki Iwadare talks a bit about arranging a PSX game's soundtrack for the PSP here, and I think the final result turned out well: https://www.patreon.com/posts/pre-show-with-11452554

I like that Curse restored the introductory section from "Azure Sky" that was present in the prototype (but cut in the final version) of Lufia 2, at least. It seems the composers for Chaos Seed didn't adhere to the SNES sound channel limitations ("When I arranged Chaos Seed's music for the SEGA Saturn from the SNES, I added some deleted sounds, especially drum, because of the lack of channels" from https://web.archive.org/web/20030501034419/http://interviews.rocketbaby.net:80/interviews_nakajima_yukio_1.html), and it would have been nice to have any deleted sound channels from the original Lufia 2 restored in a remaster, if there are any.

Anyway, sorry for rambling a bit, haha. I don't think anyone would be disappointed if there was a significant delay between reviews, considering how time-consuming it is. I'm looking forward (patiently) to your eventual review of the GBC game and any future reviews!

(By the way, I recently came across a tool that you might find useful? It splits the sound channels of various game music formats - .nsf for NES, .spc for SNES, .vgm for Genesis/Mega Drive and a few others - into individual .wav files, which you could load into audacity or something if you ever want to transcribe music from one of those systems, since you can choose to only have one instrument playing at a time. Here's a link if you want to download it: https://f.losno.co/multidumpersetup.exe .)

By the way, a coupople of small typos I noticed, if you want to fix them: :p
-'{In the case of VI, it's the Kefka tier of "Dancing Mad}]' <- You can see song title has a } at the end instead of a closing quotation mark.
-"They are. They are all steps and steps above the actual score itself" <- I'm not sure what's happening with the first sentence from this sentence? (Maybe you put it there deliberately, but I can't make sense out of what it means/why it's there.)
-"That the quality of the rearranged score is barely better than the SNES score is extremely disappointed." <- The last word should probably be "disappointing" (and I agree!).
-"What ought you to do, then, for a remastered Lufia II score? If neither Yukio Nakajima or Tomoko Morita . . . couldn't get it right" <- "couldn't" should be "could" because of the double negation, but I probably would have made the same mistake with a long sentence like that, haha.