Another good review! It took me a while to notice when I first played this game, but the piano in "Those Left Behind" shares a leitmotif with "On the Azure Horizon" (although you've probably noticed, being more musically inclined than me, haha).

It's probably worth noting that there aren't actually many/any battle themes in this game, but that the dungeon/area theme usually continues to be used when there is a battle.

I agree with the tracks you pointed out having a strong melody, and that the percussion is a bit excessive at times.

Unfortunately, it seems that Yuusei Yamamato isn't with us (at least, according to a Google Translation of this tweet:

https://twitter.com/yukio_nakajima/status/342998153743716353

- yukio_nakajima

). It seems that he may have composed a few other tracks for a few puzzle games by Hudson Soft, however (according to

https://twitter.com/yukio_nakajima/status/343026914279182336

- yukio_nakajima

). I'll link the ones I found below.

(I can't seem to find the track titled "ひとりにしてくれ", so it might not be uploaded online.)

Yukio Nakajima is responsible for the track at 3:42 here, as well:

https://twitter.com/yukio_nakajima/status/780810506525257729

- yukio_nakajima

. He's worked on the indie smartphone Sphere Knight (which has around 6 tracks), as well as another game called Summon Board (although I'm not too familiar with that).

Sorry about the long comment (and talking more about the composers than the review itself).

A few typos I noticed:
-"the results from Google Translate is often flawed" should either be "the results from Google Translate ARE often flawed" or "the result from Google Translate is often flawed" (changin is/are depending on plurality).
-There isn't a closing speech mark when you mention "Blowing the Wilderness" being one of your favourite tracks.
-At some points, you referred to one of the tracks as "One Sided Feelings" and, at other points, you referred to it as "Thoughts Unarrived". I think the latter name sounds better.

Oh, and a final note: you'll find two remixes from Energy Breaker for a fan-made Mega Man/Rockman game on YouTube if you type "rockman gaiden prayer bells" and "rockman gaiden azure horizon", if that interests you.