Another vote for being able to customize thumbnails (like SV Builder):
1) Row count and column count
2) Adding a border to the thumbnails (and style, such as square vs rounded)
3) An option to set transition between thumbnail selections (inactive border fades out, active border fades in)
I miss the fixed layout option. I have around 100 galleries on my site, so updating each from SV to Juicebox takes alot of time. Now I'm going to have some galleries on the SV layout and new ones on the Juice Box layout. I really don't want to change my layout - I like it. The only reason (for me) to change to Juice Box is so mobile users get a more consistent experience.
Where's the option for a background image?
For the Title and Caption, why did the font size scale change? In SV builder I used 18 & 12 as the sizes, now I need 4 and 2 in JuiceBox.
An option for the caption to stay visible at all times. This do-able now, but that also means the nav buttons and button bar are visible too. My layout has room for the Title / Caption bar to stay visible at all times without overlapping on the images.
Setting these options will get confusing; it would be nice to have a couple different preview options:
1) what it will look like on a website
2) what it will look like on an iPad
3) what it will look like on an iPhone