Yes. Perhaps hitting the optimum form at 45 would be ideal. So 4 would start becoming clearer at 40 and then start degenerating after 45.

Or change the motion curve so that it stays in the recognizable state for longer, like 90% of the time.

I'd suggest capping the animation duration. 90% of 10 hours still leaves an hour for the animation.

If you've got an extended clock (days, months, years, centuries, millennia), morphing could take a while.

Currently the animations all last at most 20 seconds, irrespective of the transition duration.

Came here to say this. The "pure" version of each digit should come in the middle, rather than at the beginning, of its interval.