I use Cakewalk version 9 for most of my MIDI file editing.  It's an
old version but it may still be available in the darker corners of
eBay.  Later versions of Cakewalk are oriented towards audio, not MIDI.

If expense is not a serious issue, Cubase is another program I have
used to do things Cakewalk can't do.  It is regarded by some as best
MIDI editor of all, but Cakewalk is still my favourite.  Hope this
helps.

Peter Phillips
Sydney
http://www.petersmidi.com/