This may be an unpopular take, but I'm not sure Mu will ever run faster than she did last year. It's not unusual for these phenomenal talents to peak at that sort of age (of course not all, like McLaughlin, Bolt etc), and the fact that she regressed a bit this year is slightly concerning to me. That, and the fact that she's a 400/800 type, rather than 8/15, so building a more solid aerobic base could potentially blunt her speed, which is her key weapon.
I'd happily be proven wrong on this of course, and she can still win gold medals being inferior to last year.