OK, I did some digging around and found that someone wrote a script that calls free transform with the maintain aspect ratio button already clicked. You can install the script, and then create an action that calls the script, and give the action a keyboard shortcut. Then you use that shortcut whenever you want to resize something.
Adobe should make this easier. But if, like me, you don't want to wait for them to get around to that, here's what you can do.
1. Download the script.
It's here. (I named it transformMAR for "maintain aspect ratio." If you want to call it something more interesting, you can rename the part before the .jsx. Whatever is there will be what's in your script menu, if you care about that. )
2. Install it. Installing scripts is much the same as installing any other preset. First, copy the script into the Presets/Scripts subfolder:
Mac: <hard drive>/Applications/Adobe Photoshop
CS6/Presets/Scripts/
PC: C:\Program Files\Adobe\Adobe Photoshop
CS6\Presets\Scripts\
(replace the bold with your version of PS if you don't have CS6)
Then, after you quit and restart Photoshop, the newly installed scripts will automatically appear in the File » Scripts submenu (in alphabetical order).
3. Record an action where all you do is run the script. Make sure to choose a function key in the dialog that pops up when you press the new action button. That will be the button(s) you press whenever you want to resize. (If you don't know how to record an action,
Zoe wrote a tut here on the SSD blog.)
Full disclosure: I didn't write the script. The guy who did just posted the code on Adobe's forum
here, but I went ahead and saved it to a file to make it easier on y'all. I tested it out and it appears to work just fine with no side effects!
