Have you tried other battery tests for comparison? The problem with video playback is that it's a highly specific workload that enjoys hardware acceleration. It's interesting to many people for sure, but it doesn't necessarily test the CPU, how efficient it is at generic processing.
I imagine the win in GeekBench has something to do with core count. :-) If you run applications that can utilize multiple cores well, great. But that's often not the case as some workloads don't parallelize well and PCs were limited to a single core for a long, long time. There is also the advantage of having specialized low power cores. It's like having two processors in your PC, one more powerful and one more frugal. That's just not how PC CPUs are designed. Maybe they should, at least mobile chips, but it's not magic. And the situation around integrated Intel GPUs is laughable. The 620 and co. should be dead. Certainly not mainstream. I think even more ridiculous example in Apple's stable is the Mac Mini. Even the MacBook Pro 13 has a better GPU. And that's a laptop. Against a desktop.
You shouldn't have chosen Apple. I know the Air is iconic. And Apple is popular in the US. But, if you want to run Windows, you should choose something that sells with Windows and regular users actually run Windows on it. And why not look into Chromebooks? I know cross platform benchmarking sucks, but benchmarks have to reflect what people are actually doing.