"Stuck to the sides? I reread the article and Brad mentions almost too much space between the fly and the inner."
The unnecessarily large inner/fly gap Brad mentions is along the ridgeline in the back half of the tent (shown above). Big Agnes should redesign the poleset/fly as Brad describes, which would cut weight and improve this tents resilience in side winds. Alternatively, they could modify the inner with a few extra clips and additional no-see-um netting to take advantage of this space and add volume in the back half of the tent for virtually no weight.
Where the fly gets stuck to the inner is along the sides of the tent at the bottom (shown below). You need to stake it out here, or the sides of the fly contact the inner and end up sticking to it once condensation has formed. Not doing so is problematic, because the wet fly is stuck to the inner right along the bottom where your sleeping bag is likely to be touching the sides. So 8 stakes is really the minimum and if you were expecting harsh weather and wanted to guy this tent out, you'd be at 12.
I'm not sure if this is also present in the Fly Creek UL2, but the design of UL3 is very similar in that you also need to stake out the sides of the fly to keep it off the inner. After several days of use in wet conditions, the UL3 fly material sags/stretches so much that even staking it out isn't enough, and it will still stick the inner part way up the tent over a fairly significant expanse (about where the UL2 guyouts are). This ends up being unavoidable in multi-day wet trips, and is one of the reasons why the UL3 (and perhaps UL2) isn't that fun to live out of for 2 wet weeks on Vancouver Island, despite its awesome volume:weight ratio. At least the UL2 has guyouts here, so if it is an issue after a few days of rain then presumably you could go to 10 stakes.
May I ask what 2 person tent you use?"
Currently my wife and I are using a TarpTent StratoSpire2. It's 40.3 oz all in (tent, guylines, stakes, sack), whereas this UL2 Platinum is 30.4oz presumably plus 8+ stakes, guylines, sack etc, so likely 34-35oz apples to apples.
The SS2 is a bit fiddly to set up on undulating ground, which is the biggest con. Once pitched, the SS2 is far nicer in the rain with the non-exposed inner setup, dual protected overhang doors, large vestibules and fly that doesn't stick to the inner. Living space is also much more generous, particularly the headroom. 6 stakes or 8 if you want it sturdy (which I usually do).