Using one of these in my '18 with a 40oz HydroFlask and it works a treat. I did have to wrap the bottom with the "Soft Fit foam sleeve" to get a nice firm platform.

BottlePro Cup Holder Adapter

Nice! I caved and just bought this on amazon. Works great though!

I went with the BottlePro (Amazon Link) and it holds my 40oz Hydro Flask a treat in my '18.

My coworker has these cup holder expanders and swears by them. I have them in my amazon cart and plan to order next time I actually need something.

I found the horn to be way too wimpy so I replaced the stock one with this PIAA pair.

I also didn't want to screw my plates straight through the front bumper or directly against the back bumper so I put on license plate brackets that I think make it look much nicer.

I took the advice from a bunch of folks on the subaruoutback.org forums and put in a new 19mm sway bar. It was a pretty easy install, but honestly I can't tell if the drive is better or it's just a placebo effect.

Then just a couple of simple quality of life things just because:

• ProClip phone mount that I put right over the hazard lights button. No issues with the EyeSight that I've experienced.
• Water bottle cup holder adapter to hold my 40 oz hydroflask
• Seat gap filler because my phone likes to slide under the seat