Honestly, there's no pleasing some people. When the pen was included, everyone was saying, "let me buy a cheaper SKU without the pen; I don't want it!", and now that they've done that everyone is complaining.
So far the only drawback of the SP4 is the battery life, so except if they improved it a lot I don't see the point of paying the 500-600$ more. They say it's possible to watch 13.5 hours of videos, but manufacturers tests are not trustable anyway. It would probably be more like 7-8 hours of real-world usage. Are the extra 3 hours worth the difference? Maybe, but for my usage no.
I mean, during the conference day I'm kind of depressed of not having battery any more, but with cold head I tell myself it is better for me.