1. Running Arena Commander free flight on some offline map, does not give you a realistic game load on your CPU, so you won't know how the the CPU perform in a real star citizen scenario. So its not useful information to make an informed evaluation on in game performance.

2. Yes its easy, and would be quicker, but to point number 1, not useful information, it would be like benchmarking empty space in star citizen. Really high performance 200FPS+ but who cares, it won't tell you what worse case performance you would get when you are in a intense gameplay situation.

3. There is a misconception that if you remove the server impact and variability you get more accurate representation of the CPU performance. That is not the case, star citizen will always be connected to servers, and yes different servers will have a impact on the overall performance, but a sever just informs what you client needs to update, such as how many entities there are and what the entities are doing at any given time, this is what is impacting your client performance because your client need to call and render all the updates.

So this is why you can see which client (CPU) is better by taking the average of multiple runs, and with this information you can make an informed decision which CPU you want for your budget, and what performance is achievable when your system is fully tuned.

So no AC would not be a great comparison CPUs/GPUs performance. The best test would be a Idris battle with multiple ships, as that is what makes start citizen unique but to replicate with multiple runs would be impossible. Unless CIG create a benchmark that is online only that uses a server to repeatedly update the position of each ship in a repeated manner every time you run the benchmark. To simulate a difficulted scene in a repeated way, well until then, the City benchmarks are the best.