No worries, brianmcdoogle - you made me curious so I did some hastily eyeballed (with my frankly crappy eyes) & rough measurements on the amiibo I have opened. All weight measurements on standard kitchen scale. All height measurements include the base, the width is the widest part of the figurine portion. Spoiler Alert: Smash Bowser is a game wrecker.
Smash Series:
Pikachu is 42 g, 8 cm tall, 7 cm wide from left eartip to tailtip.
Peach is also 42 g, 11 cm tall (including her crown), and 6 cm wide, front of skirt-wise.
Kirby is a hefty 43 g, and 5 cm tall and wide, measured from his shoetips.
Bowser is a broken 105 g, 9 cm tall and 9 cm wide, both from claw to claw and from tailtip to snout. Probably the largest amiibo in weight alone.
Most other amiibo are less than 1/2 of a Bowser from what I can tell! He's practically a blunt instrument.
The Animal Crossing series:
Digby is the lightest at 33 g, measuring 8 cm tall and 3.5 cm wide from eartip to eartip.
... I could go on, but the heaviest amiibo in this series so far is...
Cyrus, at 45 g, 9 cm tall, and 4 cm wide from front tip of hair to back of head.
All of the other Animal Crossing amiibo are between them in weight and similar in dimensions, although a couple are wider, Nook at 5.5 cm from tailtip to snout and Mabel at 6 cm between spiketip to snout.
I don't really know if this indicates anything other than Nintendo getting more efficient at making the amiibo & Animal Crossing characters being more similar in size than the Smash characters due to the AC games providing a more uniform scale opposed to Smash's multi-roster approach.
I still think that the detailing on the AC ones is pretty great, there are several different textures on the clothing, and the wood grain on K.K.'s guitar and stump are crazy. The joining seems less awkward to me as well. While I was measuring, I did realize that Pikachu and Kirby have likely skewed my perspective on the Smash amiibo detailing as they are mostly paint by numbers and half of our opened Smash amiibo. The paint on those two is slightly flaking in places and they aren't handled very much at all, either. I should play a few more rounds of Festival and see how well the AC paint jobs hold up over time and use. I'd imagine K.K.'s guitar strings would be the first casualty.
I'm really interested in what the second set of Animal Crossing amiibo will weigh in at, as they are going to feature wider
and heftier
characters, as well as a 2 characters in 1 amiibo
similar to Rosalina & Luma, but in a more condensed pose.
I am probably too defensive anyway, since I'm a bigger Animal Crossing fan than I am of almost all of the Smash characters (yes, really, not shocking), but it was a fun little thing to do... I won't say "science experiment" because I'm terrible at eyeballing stuff though.