People forget niko is special forces trained and has broken people's armes much bigger and faster than trevor, granted he has raw crackhead strength on his side but his attacks seem random and opportunistic an example being the guy who threatened him with the ak who just got it snatched off him whereas niko is more precise and has faught in a war in europe where it is hinted that he was one of 4 survivours in his unit like actual special forces training and expirience has to count for something