Give VideoReDo TVsuite V5 a go
use it all the time to cut clips/ remove intro and commercials
does not re-encode h264 etc - does a frame copy to the new file
That software has a 15 minute limit on cuts apparently which makes it useless for my needs.
Only if you dont want to pay
and you never specified it had to be free
Trot on
Honestly you are looking for a full featured Video editor that will re-encode your footage if you want to have a smaller file size. you can look at things like Keden live or Black Magic Resolve to do this.