My Celesta at the U looks like that, but has 3 ranks, or shelves with tone bars. As BDB said, the main adjustment is the capstan/sticker length/lost motion, however, each note has it's own damper lift adjustment made by bending the wire, and the pedal has an adjustment for each rank.
The lost motion adjustment will change the volume of each note and the damper adjustment. The condition of the hammers and felts supporting the tone bars will affect the tone and sustain.
Key dip must be even and shallow enough so the hammers don't block at full dip.
If you have occasion to remove the stickers, be sure to number them - they are individual, and mixing them up would be a real pain.
A good regulation would begin with removing the stickers, dissembling the ranks, cleaning the tone bars, changing supporting felt cushions if needed, inspecting hammers, changing buckskin if worn, checking for loose or broken glue joints or parts. The capstan nuts are prone to stripping or cracking in half. You might have to make or buy replacements. The keys have bushings just like pianos, so re-bush these if needed, but the bushings must be on the loose side, or keys will stick.
Assemble everything, check and adjust key dip, and adjust the capstans for even volume then adjust the individual damper lift as needed. finally, adjust the damper pedal at each rank for even lift at each rank.
I would welcome any additional info (or corrections) on this - great question! I had a hard time finding info on these instruments as well.