This question largely depends on personal taste and certain channels might sound better on different instruments.

The point of using different channels is more about their collective effect. In other words, it's not as important to use the same channel on any given instrument but more so about making sure that all the channel numbers are unique. That way, all your tracks will combine in a way that is more pleasing to the ears in the same fashion that tracks are combined on analog desks when their signal flows through the slightly different components of each console channel.