Everything depends on where this bike fits into the scheme of things going forward. As an entry level bike, it may not be worth it. Especially when better pandemic bikes start hitting the used market at reduced prices.

I ride 8 speed, but my stuff is old, however the vast majority of people would not waste money on that level. If you see yourself moving on in a couple of years it might not make sense to “change” cranks.

As far as chain rub on a derailleur cage “only” when sprinting, I’d probably live with it. There is no guarantee that the new crank won’t do the same.

John