Sir_Ivan cool, thanks...
Here's one potential issue with that approach in case its helpful for how you think about how to design a zoom-like option in general...
I recently had to do a ken burns montage with images that were not all sized the same and had varying aspect ratios. So before applying keyframes for zooming, all the photos had to be positioned without black bars (love the "fill"command for this, BTW). So, the % preset idea you mentioned might get kind of fiddly because the starting point for each photo may vary and not be 100% to begin with...
All to say, if excalibur where able to facilitate applying "zoom" by a percentage that uses the initial scale setting as the basis, that may be interesting. In other words, zooming by "10%" would take a clip scaled at 100% to 110%, but a clip already scaled at something more arbitrary, like 41%, would go to a Premiere scale setting of 45.1%.
Also, I hear you about things getting too tweaky. That said, if it were possible to auto-create keyframes on the first and last frame of clips, that might be helpful. Though i realize this may be too niche. I'm new to premiere, so i don't necessarily have an appreciation for how much some of these ideas may be useful to others (or if there are other/better ways that already exist to do some things).
