What I'd be concerned about with all-in-one is drying time, and problem with bits of and/or grit sticking between shoe and foot when used damp, and, if using flip-flop style shoes, the level of grip between foot and shoe on non-level ground.
Any stability advantage for inner first tents really only applies to those that have continuous deep pole sleeves. like a Quasar or VE25.
If the inner attaches to the poles with clips on tape loops, like a Hubba Hubba, the inner first tent is structurally the same as an outer-first tent that has the inner attached by toggles on tape loops. Such a tent may even be less stable than the equivalent outer-first tent, as external guys won't transfer load to the pole structure so well, just being attached to an outer draped over the top of the poles.