Aside from Counter Instinct which is the best skill among all Yuls, DEs have naturally high STR so they can EASILY focus on adding up on DEX. On the other hand , Elves already have decent DEX but since they want more DEX, they will be neglecting their STR. With the new dyes this was addressed a bit.
Do you honestly think those Ghost Sentinels are still adding STR? With the new dyes, yes... but I'm sure DEX is their priority.
And another good point that I got why a Yul must go all DEX. As we know, STR relates to P. Atk and DEX to Crit Rate. There are A BUNCH of items that you can use to increase P. atk but there are only FEW to increase DEX.
I say 100 DEX and Option 2