about modified valve body - I wrote a bit here -
Tuning 5EAT
it is from Russia - B@tman. For 5EAT he has like stage 1, 2, 3. (For Tribeca he suggests stage 0.5 - for me it was a bit enhanced, so - 0.5+
DDD ) Guy has reputation - has tuned (I believe) all variations on 4EAT, both generations on 5EAT (also has done 5EAT "relatives" on Infiniti) - may be something else which I am not aware of.
HexMod worked only on TG5C (as far as I have read). I really like his posts.
Stall in torque convertors - I consider myself more like "time attack/sprint" guy, not really drag practitioner
)) (though as a testing procedure - pretty good). So - I value more responsiveness.
Suspension tuning - since I am not your average "soccer mom" in Tribeca, I want it to behave more "sportiish" - so, some adjustability might be useful. for nonadjustable setup - I would have went with Bilstein B6 (if those were available, even stinking nissan rogues have B4, B6, B8... but not tribeca)... Anyway, I will make cad drawings of struts and at some point of boredness will try to find something matching from other cars
Now - I have ability to "grab" custom spring rates and 20click adjustability (rebound) on shocks. According to Flatout Suspension - it is possible to rebuild them on your own or you can send struts to them to rebuild with different valving.
Deleting AVCS does not give any power. it just shows that "deleter" has either low intellectual abilities, or VERY specific requirements(which, to be honest, I can't really think of). It is technological step "backwards". A long time ago - when guys tuned engines - when they couldn't get camshafts with "sportier" profiles - they made vernier pulleys, to rotate camshaft relative to crank thus moving peak up or down (as they wanted/needed).
Novadays - AVCS allows to do that by punching in numbers in maps and there is no need to get your hands dirty, do wrenching for 4hours to get to the point where you can test your setup...
About SUBARUs intentions -EZ30D(or how some prefer to call it EZ30R) - power per liter is ~81.(6)hp/liter. EZ36D - it is just 71.(6)... Other N/A Subaru engines - FB25 (way more modern than H6) is 72.8hp/liter. EJ25 even less...FA20D (brz engine < 2017) is 98.5hp/liter, 2017+ it is 102.5 hp/liter.
So - at least 3.0 liter engine in Tribeca is a tiny bit sportier than all the rest, but still not as sporty as BRZ engine
There are rumours that EZ30D was developed together with Porsche people (though - I haven't read it in any reputable source...may be again - bad researcher
).
About COBB - you mean their kit for Tribeca in 2006?
2006 Cobb Tuning Subaru Tribeca - Performance Tuner Road Test - Motor Trend - it is technologically the same as Raptor-s (centrifugal type). but I like their shortened intake pipe (probably Subaru-style hood with opening above filter would be helpful too
unfortunately - not much technical details