Now before I get started I just wanted to say that I don't hate that Tom Holland is the new Spider-Man I like The casting choice so just getting that outta the way. The reason I think Miles Morales should be the new Spider-Man is not because of the race thing either here's why he should be the new Spidey.
We Get Fresh New Stories
With Peter Parker as Spider-Man again we are going to have to watch his origin all over again we see him getting guilty over his Uncle's death, we're gonna see him push away another girlfriend and there's going to be another slow-motion fallingdamsel-in-distress scene where Peter catches her at the last second, and we know all of his abilities they could add some in but we're still getting the same Spider-Man we've seen in the last 5 movies.
With Miles however we get to see new things in terms of character, story and abilities. With abilities we have camouflage, the venom blast, enhanced spidey-sense and immortality yes that is a side effect of the Oz formula the stuff that made Miles Spider-Man so that could be fun to watch. In terms of character you could look to how his Uncle is a thief which may bring up conflicting emotions should he be the good guy and put the criminal away or should he should he stick with family and let his uncle get away not to mention the guilt of Peter Parkers death and following the legacy of a great hero as Miles got his powers while Peter was still Spidey.