Several years ago, I was so appalled at the standard of crosswords in a local freebie called "PubScene", that I offered my services to provide a better quality product.
I ended up providing cryptic crosswords for close on 7 or 8 months. I used to construct thematic crosswords such as those that appear in "YOU" magazine (but better)! I used a crossword completer to maintain the quality iof the solutions right to the very end. I still have a pile of the magazines containing my attempts!
Clues were constructed so as to be solvable by the reasonably gifted punter out for a couple of drinks with his mates. In all that time, no one person ever won the prize twice!
I wish you "Good Luck"