OBJECTION!
Sorry, I couldn´t resist.... Alright, back on topic:
A full blown piece of orchestra-music doesn´t fit into pokemon reborn yet or maybe not at all. In terms of music, the next battles are pretty much covered, since most unique trainers already got their themes. The only ones who don´t have a theme yet are the members of the elite four, Lin and the champion and some others I don´t know/we haven´t seen yet.
And maybe the legendary-pokemon will get their own themes, but that´s not for me to decide, so I don´t know. Maybe they get that music you hear while battling Ditto-Arceus? ^^
...And maybe the next battle against Fern, [spoiler} who sided with the meteors,
but I guess we´re going to hear the same rival-theme then.
I think Solaris is going to keep his Cynthia-Remix too, I´d really love to hear that while laying a beatdown on his Garchomp and both trainers share their signature-pokemon, so I guess he´ll keep it (Wouldn´t make sense for him to get a new battle theme I think)
Up to now, the battle themes had some kind of techno-feel to them anyway. I know, it´s not techno, it´s something else, some kind of electronic/piano-stuff, if you know what I mean. I´m no expert on that stuff .___.
...And those were all remixes to pokemon-themes. On the overworld there was KH-music used,
but maybe Ame was out of music that could be used, I dunno. It fits that place and the atmosphere anyway.
Music from Ace Attorney is always awesome, but it´s not really music you´d expect to hear in a pokemon-game.
And overly epic Orchestra just doesn´t... fit into this game.
Except an all-deciding battle against a Pulse-Arceus Lv.200 while the world slowly gets destroyed, then it´d be f*cking awesome and I´d love every second of it
And if Ame uses the original music from said games, there might be trouble with copyright (I´m no expert in this stuff, so don´t quote me on that...).
My thoughts are: If there should be any overly epic music, then do it like Final Fantasy VI. You hear ordinary battle music and some really nice music in-between, then right at the end you get the four-part epicness that is "Dance of Madness" for the last confrontation. It´s not up to me though, I can only throw my thoughts around until my mind goes blank xD