Rose Cat's Rambles

Hi, all, I'm finishing up a fic and wanted to check some words and terms for appropriateness regarding Britspeak -- specifically, whether Tenth Doctor would say/think them, or are there better alternatives?

1. "riot" (hilarious, funny)-- as in the phrase, "he's a riot," for example going with "right laugh"
2. "hilarious"
3. "in a nutshell" (essentially)
4. "clear-cut" (obvious) I'm going with "clear," the phrase in question being "the choice is clear."  Does that sound OK?
5. "over and done with"

1  (guess not) and 5 actually sound like Britspeak to me ... opinions, please?

(Crossposting to dw_britglish)

Thanks for all the helpful responses! I'm going to post the fic now. If I can make it work this time, that is }:(