Oranges are junk compared to Bilstien HD. Maybe you should research how stiff HD and stock springs combo are before you poo-poo how soft you think they are (cause they aren't). If you don't want to lower your car that's the best option. Or get coilover and run the high...
Here is my page on o2 spacer I made for my car. I used 2 sparkplug anti-fouler spacers for about $5. You only have to drill one open with a 1/2" bit to fit the O2, but it's so easy and only takes about 30min to fab up.
Everyone I know in the Subaru community runs T6. I've run it in my lightly modded '11 turbo Forester since the first oil change and have 40K mile on it.
The biggest issue with it is a little hit to MPG (about 1-2MPG) T6 is 5w40 and the Forester required 0w40. The main reason most car manufactures are using 0 weight is to squeeze out every last MPG that they can easily and switching to the thinner oil is cheaper then redesigning a motor/car. Personally I'd run thicker oil for the extra protection.
Had a leak under boost that was causing CEL for overboost, but I noticed it was only at high PSI. After finding the source, found a little slit in the WGA diaphragm. I swapped out Kinugawa adjustable w/7.3psi spring, back to stock and shortened up the adjustment arm. I also like the WGA with a lower pressure spring (4psi) and a lot of preload vs. (9psi) and very little preload on the WGA. When I rebuild the Kinugawa I'll throw in the 4.3psi spring and wind it up with preload. Also threw in a new AC Delco TCV. My original one was almost 8yo, figured it was time for a new one. Reset the ECU and took in out to relearn/adapt to the new setup.