I have 46.5 hours and I can't think of what else to do. I rewrote the first 23, basically, and then skim-edited the other 17 and straightened out the plot, removing a few chapters... but I'm sort of stuck on what to do now.
Any tips?

If you rewrote the first 23, then these are a first draft. Have at it!

Otherwise, if you think the big picture is fine, then start from the top with the line edits.

I would love to have your problem.

Since you have a week left, it might be a good time to hand the first few chapters and your outline over to a trusted Beta reader and see what she/he says.

I got this idea from the 'day by day, hour by hour' thread - reading your story aloud and listening for things that don't sound right. :)

In your case, Arianna, I'd suggest possibly starting to read just at the point where you started skimming, because it has forced me to get more deeply into the parts that I've just skimmed over before.

And keep a beverage handy to keep your throat somewhat happy.

If I had that chance, I personally would be doing an intense line-by-line, you could do that, or something else too. I have the opposite problem - I know 50 won't be enough!

You could also look at some more big picture things (partially inspired by the "Week by Week, Day by Day" thread)
- characters: make sure they have flaws, internal conflict, and voices different from each other in speech
- plot: make sure it flows, there aren't any major holes, and it goes up and down enough (i.e. there's no big lulls without some action)
- prose: take out long-winded blah-blah-blah sections, vary your sentence structure, etc!

Hope those suggestions help! :)

I would suggest looking for those words or phrases you use too often.
There are tools to do a word count of every word in your doc. That can point out what you use too much.
and there's the standard:
was
were
very

etc.

to look for...