If we look at some of your skills…
Fireball - melee deployment, small aoe with fixed aoe ratio
Firewall - melee deployment, multiple single-target hits
Enchant Fire - buffs your AA, which is a ranged single target hit
Shrink / Swell Body - melee cast, tiny AoE
Pole of Agony - melee deployment, tiny AoE, benefits from displacement
Invocation - buff that creates single target, single hit things
Dark Theurge - buff, melee single target hits
Evil Sacrifice - still single target hits afaik
Yup. Linker’s definitely worth. The only skills that do not greatly benefit from it are Flame Ground, Reversi, and Mastema