Hi Brian,
Although I don't have a suggestion to get around the limits of the "Standard" version -- the steps taken by the script you linked are not exceptionally time-consuming.
The gradual selections are obvious near real-time and although the first optimization takes a couple minutes for a couple thousand photos, subsequent runs are very fast.
One key thing to consider / speed the process: When optimizing -- the script
does not check the boxes for B1, B2, K4, P3, P4, Adaptive, Covariance, or Additional Corrections (for the first two gradual-selections). On the third gradual-selection (Reprojection Error) you will select the Adaptive option (disabling all others). With these settings, your first two attempts should be expedited and your third attempt will be faster, despite the extra processing, because the images are much more optimized prior to the operation.
In short, while I agree,
it would be extremely valuable to add "Gradual Selection" to the "Batch" feature, at least you can replicate this script without too much time.
Also, this script appears to use Reconstruction Uncertainty at 15, Projection Accuracy at 15 (typically I believe 5 is a better range for this, if it doesn't remove too many tie-points), and Reprojection Error iterates up to four times to reach 0.20 starting at 10.
Sorry I don't have a better option, but I hope this helps
