Alright, I'm just going to say one thing on why I find it easier to make a large sprite vs a small one: more space. You can have better looking poses, more detail, and it's easier to FIT all the detail in. There are a lot of details that I'm not sure how to cram in the RTP sprites that I can fit in larger ones. While I do prefer making all my sprites RTP since it takes more TIME to make larger sprites, I find that larger sprites are easier to make because I have more space to work in. for example, spriting a 60x60 character portrait is SO much easier than spriting the hair on an RTP sprite. It takes more time, but is much easier.
However, due to the amount of posing involved in animated sprite battle systems (ABS, SV, or whatever), it actually takes me a heck of a lot less time to do a side view battler's poses for a given move than it does to make the ABS battler's same moves. While side veiw sprites take more time (about 1.5 times as much), a single animation for a side view sprite is generally 4 frames of animation. Whereas a ABS animation is 4 frames for 3 different angles (the front, the side, the back). If you think of it mathematically where SV stands for the amount of time a single side view frame takes, RTP stands for the time a single RTP sprite frame takes, SVAnimation stands for the time a single animation of a side view takes, and ABSAnimation stands for the time a single RTP ABS animation takes....
RTP = 20 (I just gave it a number for the sake of argument. The time just depends on what kind of pose you're doing)
SV = RTP * 1.5
SVAnimation = SV * 4 (4 frames of animation)
ABSAnimation = RTP * 12 (12 frames of animation)
Now let's compare the results
SVAnimation = 120
ABSAnimation = 240
According to this, if it takes you almost twice as long to make a single frame of animation for a side view battler as a frame of RTP animation, it'll still take you twice as long to make a full RTP ABS battler's animation. Even if you make enough animations in a side view to be taking advantage of all the animations needed to use all of blizzABS' features (a charge animation for each skill, a skill animation for each skill, and the same with every weapon and item, as well as the running, sneaking, and jumping sprites), then you'd still spend only half the time making a complete side view battler.
Just my ten cents. And I'm customizing all the animations for myself in my own game using an ABS, so I DO know how long it takes to do these stinking animations (and so does blizz, as he's waiting on me to finish them

)