Hello,
The first aspect we have to choose is not the langage or details as using float or int for rating...
The main decision is :
Do we make a optimized version of Serate (clone or optimization) with a very near rating (perfect matching is not compatible with high optimization)
Do we promote a new rating plateform that implement in a first step a rating near from Serate but can evolve with new solving techniques like SK loop...
This choice can be made by a team deeply involved in Sudoku development...
I would largely prefer the second choice, because when I look in detail at SudokuExplainer source, it is very difficult to extract the precise rating rules from the source.
Best regards
Patrice