Those EMP rings might work like loot in hack'n'slash games.
If it does work like that we'd roll for the traits on the ring then roll for the numbers of those traits. As an example: if i roll a ring with ATK up, it would roll between 500 and 3000 to determine how much my character gets from it.
I'd have to see the droprate of those blue chests to determine how awful this really is. I'm also assuming that when you give a character a ring you can't take it back and give it to someone else.
That's small HP up from the Ygg cane.
Actual boost that matter will probably go up by about 2%.
Big Ygg get
Not even a SL10 to 15 weapon gets that big of a boost unless it's massive.
You are right though. The grind is very disproportionate to the actual benefit.
Since Tia bolts are only medium ATK up i imagine it's 1.25%.
Going from SL5 to 10 is a 5% increase, SL 10 to 15 is 2.5% which logically would mean that SL15 to 20 is 1.25%. Which also means big ATK is 1.50%.
So yeah not great.
Seems the best things to grind from this patch are the EMP rings and the uncap on magna summons.