Okay, I think that we're on two separate lines here. I was talking of Enlightened Tutor as a Wishtarget for Cunning Wish and certainly not mainboard.
The reasoning behind it as a wishtarget: to solve things Cunning Wish can normally not handle or to get something when there's no immediate threat to handle.
Well, I'm not thinking of CoW as cannon - I've cut it before but that was a horrible decission so it is back in... there's a reason that people consider it cannon after all.
There's very little you actually need to counter that you can not handle otherwise (EE, WoG, StoP). Also, in the matchups where you need FoW from turn1 onwards (combo) CoW is pretty bad anyways so that you could just not play it...
Also, playing CoW turn3 assures that you'll get a constant supply of lands to actually play all those expensive, strong spells (with Counterspell backup or Daze proof).
I don't understand this, probably because of my English. I'll interpret the 'put the premium on deck space' as 'streamline' or 'don't include chaff'.
Now with that said, I still don't understand your point: Tolaria West is just way too flexible and actually allows you to cut down on those cards that you need but are only good in some situations (e.g. Wasteland) by increasing the virtual count of them - you actually trim the deck down because it can also get you something else than the thing it replaced, something that is not situationally good because you get to chose what you want.

