H Stock Setup

I ran my car completely stock last season but I'm looking to make it competitive for this season in HS and I have a few questions. I know tires are the best things for performance but the FiST has a rollover risk and I didn't want to allow myself to go too fast in slaloms without upgrading the suspension first to help combat this risk.

I had planned to go KONI Yellows in the front and rear with an Eibach rear sway bar to start. I have read of people swapping the front sway bar instead but that seems to have mixed results and I'm more concerned about reducing under-steer than eliminating a bit of 3 wheeling.

What I'm wondering is are the KONI Yellows in the front worth it? I do want the best setup for HS (need to keep stock springs) but I've read people have mixed results, KONI doesn't even say they fit the FiST (says it fits non-ST Fiesta), and I read a review by another user on this forum that has tested combinations of yellows, oranges, and stock shocks and found that the best setup was simply stock in the front with yellows in the rear. Any advice on which are the best shocks to use and if KONI's are the best to use all around, what stiffness/softness adjustment?