Scale is absolutely fine. Scale gets +1/+4 with each upgrade and plate gets +1/+5 and starts a little higher. You're much better off not throwing away upgrades you put into scale in order to make the switch. Now, if you have scale +4 and find plate +3, and you have upgrades to burn, sure, make the switch. Those armors at that point are about the same, and putting upgrades into plate is better.
With a ranged class, I sometimes beat that game with just chain mail. With melee, you can beat the game with only +4 scale. You just put more upgrades into weapons and wands so you kill things faster or have good utility. "The best defense is a strong offense." (Unless you're playing berserker, which you should not do except to get the badge maybe.)

this was my last berkserker build for example and it pretty much compliments the endure crown ability, and additional 50℅ damage with so much shielding is a pretty great deal, like it literally saved me from dying(thanks to the endless fury talent) due to the damn great amount of shielding i got and if evasion is your problem then just defense augment the armor