Aiming for a low-spender deck, but...

Hoo! A consultation about raising Yuldis, the cornerstone of the Verdant party, I see. First, aiming for 3-star awakening to increase buff targets is reasonable, with the ideal being 7-star awakening to boost buff amount. If you also get their exclusive weapon, your defenses should become rock-solid, hoo!

I'm not sure how much 'minor spending' you mean, but I think un-limit broken is sufficient. If you're going to break limits, it should be up to LR. While Yul naturally accumulates more stacks the longer they survive, so a higher limit break is better, I think the Green team requires the attacker to be fully limit broken and fully meta, so prioritize that.