Over Used Words

I'm a genre hopper. I'm currently writing in crossover YA, but I've hopped from light paranormal suspense to YA fantasy to time travel romance to historical romance to metaphysical nonfiction. Being a hopper I've written for several different publishers. I'm with a new publisher and with this publisher I'm required to do pre-edits. Since several of the other Downtowners write for Muse It Up they're familiar with how this works. I've never had a pre-edit work sheet before so this is new to me. One of the pre-edit requirements is looking for overused words. Its a good requirement. It makes you tighten and sharpen your writing. It's also not quite as easy as it seems.
For instance, what do you use in place of and
as
as if
then
about
were
but?
Gets tricky doesn't it? I've been doing some research on these little words and find some of the substitutes just bring in other words on the list or use 'ly'.

Some of the substitutes I've found:
As=when, while
As if=in all likelihood
Then=next
About=of
But=yet, though
As you can see, the subs will work sometimes but not all the time.
What words do you replace with when you run across words that over used? I'd love to know.