I noticed this at times as well
Flatman, mainly when seeing the slap-stick and accident-prone parts moments, most of them of Usagi either falling down or freaking out or getting scratch by Luna(seriously, that happens allot in this episode!). You had more of a calm face Usagi then a anime freak-out or funny face, which was strange compared to both the original anime or even the anime, but it ok in my book cause the accident-prone parts still had their moments, especially Usagi's Sailor V Kick which hand fall face to it.
So Yea, the tone in ways does seem more serious, but also has a lighthearted and even glorious feeling more to it a well too. In the previews we still seem to have a funny moments too. ;-)