Personally I don't care to have either MP or scenario abilities with Civ3. I am actually happy that they didn't include these in the original edition if it would have meant that it cost more. I don't want to use them and don't want to pay for them.
I bought, and extensively used, Civ2 and never felt the need for MP or scenarios. And from what I picked up along the way I would have wanted to upgrade to Civ2 Gold, at least, if I wanted these. So I never expected them to be available with the original release of Civ3.
I am quite happy with the money I spent the day Civ3 was released, (I actually got to the store before they had unpacked the game so I had to wait awhile), and will more than get my money out of it with all the hours it will occupy. I would like one more patch to fix the obvious errors in the game but I have been having fun playing since day one.
The above are my thoughts as an avid player. Now, if I put on my CPA/business advisor hat.....hey, same thoughts. If some players want more abilities, get the base game out for most of the people and then release an upgrade that will satisfy those that want more at an additional cost. Don't make the many pay for the few.