Just discovered what they meant with "everyone" version
So, the breakdown of The world is all one!! is this:
1) First Unit - HMH
2) Second unit - MCT
3) Third unit - TMY
4) Ryuugukomachi + Ritsuko
5) Allstars, everyone got their own solo part, and there are parts where everyone sings simultaneously
6) Original Karaoke
7) Everyone: the one sung in 5th concert, with "everyone" as in "the idols and their fans singing together"
Yeah... "everyone" alright.... Dear God, I was hoping we'll get to hear Kotori Otonashi.
Except the last one, everything is in M@STER version. This is the literal manifestation of "redundancy"
M@STER version of The world is all one has too many repetitions for the BGM. The same notes are repeated over and over for the entire song. Basically it's two of it combined into one.
I like the original version NBGI embedded into their website. Everyone sings together for the entire song. Good thing I managed to rip it

I was actually hoping this is the "everyone" version
EDIT:
SMOKY THRILL M@STER version sounds like it's coming from a radio tape. For some reason the voice is VERY CLEAR, wile the BGM is... well... it sounds a bit noisy, maybe they dithered it.
Then again, this MIGHT be my copy.
And I don't like the M@STER version. There's just too much filler here, and I mean it. I can count up to more than 1 minute is spent in filler, unlike the one in PV where it's 100% action
Fun Fact: I actually counted the time the filler is used, and it's more or less exactly one minute

. That's one minute reduction for the song
To be frank, these two (M@STER version of The world is all one!! and SMOKY THRILL) are the biggest letdown after my CDs' case cracked

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Okay, so here's a (not so) proper verdict:
The world is all one!!1,2,3,4,5,6: I don't like the M@STER version, and I love "everyone sings simultaneously" better than "everyone gets their own part", much like THE iDOLM@STER from MASTERPIECE 05. But there are so many options to choose from, so your mileage may vary (especially if it has your favorite in it)
7: Well, if you didn't participate in the concert, here's a recording of that. Other than that I don't see many uses. You can even hear the hall effect. Looks like they simply record the whole dome
SMOKY THRILL1:
To be frank, personally this is a letdown. Like I said up there, one minute of filler, not counting the occasional short burst of fillers. If you want a godly version, go download the 4th PV and record that SMOKY THRILL there
This could be biased because frankly I don't like Ami/Mami that much (they have their own area is what I'm saying) so with Ami singing solo in some parts it kinda breaks the harmony, since Azusa and Iori's voice are nothing like her. But even then I like "everyone sings simultaneously until the end" better than this one
2:
This is a good song, and once again feels helluva lot like an anime OP. Personally I don't like Ritsuko much, but I like her here
4:
This is a very good song, slow and soothing in contrast with the other two. And for some reason I feel this is a Christmas song. I didn't think the combination (Miki, Yukiho and Yayoi) can pull this off but I'm wrong