MidiPlayer 6.6 is out,
https://falcosoft.hu/softwares.html
so I downloaded some 30.2 gigs of ziped and cd rom midi collections most all of it off the Internet Archive.
Should take a long time to sort it all out.
If you want a more sophisticated player
https://www.synthfont.com/Downloads.html
I think is a bit overkill.
But Spider Midi Play Pro is now completely free, and I think it will grow on me.
https://spider-player.com/download
I put Mysung.sf2 into the regular version and it did not even hesitate. That is over 1.5 gig sf which is really nice.