About hybrid armor...

Yeah, but you are getting full value from each flat mod. An ES chest can get a max of +145 base ES. A hybrid can get the same. An evasion chest can get a max of +400 base evasion, a hybrid can get the same.
The max % mod is 120 across the board.

So Vaal Regalia with base 175 +flat 145 x220% = 704 ES from the two mods.

Assassins Garb with base 525 +flat 400 x220% = 2035 eva from the two mods.

Carnal Armour with base 251eva +flat 400eva, 105ES +flat 145ES x220% = 1432eva 550ES, for 70% of the evasion and 78% of the ES of the respective pure chest types.
To not have to sacrifice an extra affix for this would make all hybrid gears extremely unbalanced.

Yeah, when it's like you put it, it's ok. Rolling those 3 affixes is kinda hard I think or next to impossible and not really so awesome, since you can't get life. That's why non hybrid armor that rolls life armor/ev and % multiplier is superior. You get a lot more stats and life. That's why armor/evasion hybrid is the worst armor you can get. Can't make it good. Es/ev is ok i guess since you don't need life if you run CI, which in most cases you will be running. Armor/es is well... not so good and ugly. Only works with certain builds, that are very limited. You are better off running armor on your headgear and es on your chest having life on both. If you are CI this is not a problem. It all comes to this - if you want to run hybrid - you go CI or bust. That's why armor/ev sucks, because evasion sucks.

A set of perfect hybrid armor (EV/ES especially) is ridiculous.

But if the armor isn't perfect it's pretty much worthless.