I am just relieved that they didn't use the"Guardian of Forever" as a time travel device. How many times has that planet been revisited from TAS to present in fan fic and fan films?
I personally don't care if they use the Guardian of Forever or not. PII/NV used it in "Mind Sifter" and I think that was a much stronger story than "Divided We Fall."
I want them to focus more on the basics of storytelling than any specific plot device. After all, is it any better that they used Kirk hallucinating two episodes in a row rather than going to something other productions have used before but STC itself hasn't?
I didn't really see this as a mere hallucination but as a Matrix-style virtual reality constructed by the nanites that was based on the computer library and other elements. Also, unlike "The White Iris", it was a shared experience more akin to a Holo-adventure, but I'm definitely glad they didn't go there. They really need to shelve that in future episodes, particularly after they build their planet set.
I think it was very clearly implied in "Divided We Stand" that if you died in the simulation you died in reality, as Kirk's leg was literally dying after it was removed; therefore, the risks to them were the same as in the real world. That's the main reason it held my suspense and why it mattered what happened to Kirk and McCoy. In this episode, there was a legitimate outside influence at work and I thought that the symptoms were due to a more logical reason than the reason given for Kirk's heart failure in "The White Iris".
With that said, I think they could have followed through and made a stronger case of tying the virtual world to the real world.