I like Apex series as well.
If we talk about Maximus IX Apex and Rampage VI Apex than OK.
But Maximus X series Hero have some advantage, if I saw good, better onboard audio and PreMounted I/O shield protector from electrostatic.
I think all ROG boards in future class Apex, Formula, Extreme should have PreMounted Shield.
I don't know why they use only on Extreme boards and now I see Hero have.
Off course I'm always for E-ATX.
Or mATX if someone want to build some nice small RIG with i7-8700K.
I always dream such small powerfull RIGs with all Intel-ASUS stuff, ASUS board, GPU, sound and Intel's SSDs and CPU.
It's bad because ASUS refuse to build high end mATX motherboard with same power section as Hero and Formula level with PreMounted I/O shield, best chockes used for high end board. That would be expensive board but there is a customers among people with high budget who want to invest in smaller PC.
mATX is still enough for SLI + dedicate sound card.

You should compare better Hero and Apex maybe.
It's not bad at all... I think she will be best seller for Z370 ROG Class.
Apex is little nicer.

For my RIG because I have sound card I would choose Apex. But I would like to see protector on I/O on my board.
Look far better.