Too Funny.
If you are looking for support in your decision you are probably looking in the wrong place.
Lighten up fellow smarties. It sounds like they need some vindication not dirt throwing.
You say that you should buy a Yaris but it sounds like your emotions say otherwise. I sat on the fence as well. I agonized the same points you made and just made the plunge and got my smart anyway. I figured that if I hated it I can always sell it and buy something else off the lot without losing anything. That said, I absolutely, positively, love my smart. Every single day since I picked it up I have a smile on my face when I drive it. I am getting 38-42 mpg around town and laughing all the while.
To your points:
Better car..........in whose opinion? Toyota has impeccable build quality but so does Daimler. I have had many a Toyota and this car is built every bit a good IMHO than any car in it's class.
More Room..........where? In the front seat? No. I don't fit in the Yaris very well. I do however fit into the smart. It seems that the Toy is built for smaller and shorter framed people whereas the smart is built to fit larger sizes (in the front). I also think the egress is better with the smart. Sure the Yaris has a backseat but I do not use it and I can put a dozen grocery bags in my smart. So for me the backseat is not that useful and lets face it, who would like to sit in the back of a Yaris for any length of time anyway?
More power.....how much do you need? The car will do 90 easily and truthfully, if you need more power you should be looking elsewhere than either of these cars. The car has sufficient power for my taste and actually surprises me daily.
Less Expensive.......by how much? They really are so close that either is a great value today and will likely retain both their resale valuse for years to come.
Some other points to consider. Side airbags, tridion cell, green manufacturing plant, color chang-ability, go-kart handling, traction control, panoramic sunroof/convertible options, a little more mpg.
I think both are wise choices in todays economy and you would be happy with either for much the same reasons, so why not live a little and go with your emotions? Cars should be part of putting a smile on your face every day and mine does that in spades......