Problem 1 works fine
Problem 2 (will happen if you have 2000 options. but you can divide it into main category & sub category so that only few options will show up if 1 main directory is selected)
Problem 3 can be solved.
I have 3 years of experience in Google SHeets & Scripting. I can help to separate/combine excel sheets, import data from other sheets, prepare charts & clculations, dashboarding, moving data and application of pivots, formulas & formatting.