gee thanks Warner Music Group

So one of my YouTube videos got pulled for having Rossini's public domain music in it, because it was on the Clockwork Orange soundtrack, which Warner Music published.

Anyone know a way I can play back a MIDI file (specifically the Thieving Magpie) without it sounding like utter shit the way it currently is? Like a way to play back classical music MIDIs to sound just as orchestral as they do in real life?

I know FL studio allows you to import midi files and change the instrumentation. Maybe if you had one of those huge orchestral sound banks, and spent a little time adjusting attack decay reverb etc, it would sound vaguely similar?