Just upgraded from 4.1 to 4.4.2 -- questions about phone app, Hangouts

OK, so I'm loving a lot of the changes in 4.4.2. I think the white icons are really nice, my Nexus 4 feels snappier than ever, and unlike 4.3, it didn't completely destroy my phone in every way. Not completely destroying my phone in every way is one of the best perks, admittedly. But I'm liking the other stuff.

I do have a few questions, however.

1. The phone app -- it's white. Very white. The rest of the OS is black. Very back. Is there a way to change this without installing a bunch of stuff? Some settings I'm missing? I don't get why it's such a drastic difference from the rest of the UI.

2. Or is there a way to change the rest of my UI to ... white?

3. Regarding the Hangouts app. Is this expected to replace messaging in the end? I understand it handles SMS but I tried using it a bit on my previous version of Android and found it to be weirdly lacking in settings. There was no way to disable video calling altogether, and you could only swipe to archive, not to delete. I don't want to archive my SMS and I don't want to archive my chats. Has that changed at all, or should I just stick with the default messaging app, of which I have no complaints?

Thanks ya'll.