Very nice project Art! Specially when considering the 'time crisis' in which you had to make it!
I do have a suggestion, but am reluctant to share it because.......if you already know it, and didn't feel you had the time.......well, please forgive me? Otherwise, it is a good technique if you are unaware of it and very easy and classy to accomplish.
Suggestion for Border stamping: First stamp a single stamp impression into each corner at a 45 degree angle, in each of the four corners. Often a different stamp design is used for these 'corner' stampings.
Then start from one of the corners and start stamping with your border tool, until you get about four or five impression spaces from the next corner, then stop. Because, now you want to 'plan' the spacing for the remaining impressions so they 'fit and fill the space left' , and you end up at/near the corner impression. I 'plan' these final impressions by lightly walking the tool to get a feel for the spacing (adjusting the very small space between the future impressions until they will 'look right') then stamp the remaining impressions out to the corner impression.
The first time you may feel a little nervous and might even think you need to measure or something. But have confidence, this 'getting close, walking imaginary impressions, then finishing' technique is actually very easy. It results in very nice borders, evenly spaced out as far as the eye is concerned, quickly done, and takes care of the corners nicely.
The 'hints' I use are: Don't let the stamps actually touch each other when you first start stamping. Leave a very small 1/32 or so space between tool impressions . Because, later when you try to fit the remaining four or five stamps in, you again do not let them touch either. This is done so that you can expand or contract these final spaces and the eye will be fooled into seeing them as 'all equal' (because ALL impression have some space, but the Final four will have a little more or less space - to make them fit.
Not sure this will all translate in writing, but hope it does and help you or some other reader. David