Hello @Darkowl, I'm not knowledgeable on the intricacies of Force builds, but I did find this lengthy guide that includes a discussion of potential S-Grade Augments to target.
From my quick skim I didn't see much on regular affixes aside from a brief discussion of the Phrase augments. In general, if you play group content where Jellen is often applied then Phrase Decay becomes very appealing and is super easy to affix (it's the Augment Factor (SAF) on any Basilisk series weapon).
Assuming you're going for 8-slots, other usual suspects include trying to make Guardian Soul and then something like Phrase Decay/Mana Reverie on a 2-slot weapon and then moving them with 100 Transfer Passes while adding Grand Casting via capsule. Alternatively, if you have the passes to spare, you could also move Exceed Energy + Divine Order and add a capsule for the 3rd augment. However, finding a weapon with those 2 affixes is super rare so a more feasible strategy would be to find one with Exceed Energy + the Mark augment of your choice (e.g. Mark Courage) and then add a 3rd affix via capsule.
If you're on a tight budget you can easily affix Astral Soul, Casting 6, and Phrase Decay via Augment Factor from 8-slot weapons enhanced to +35. Astral Soul is on any Ray/Union series weapon and Casting 6 is most easily obtained from any technique/casting weapon in the Dim weapon series. And if you don't want to use Phrase Decay you could replace it with a cheaper capsule like Graceful Casting, another cheap affix via SAF like Doom Break 2 (any Ceres series weapon), or an affix you make from scratch like Shiva/Varuna/Duminus Glare using 8-slot fodder weapons.