Having a quick look at ChessMonitor, it looks like much of the analysis tools mirror what can be found on Lichess (unsure about Chess.com). Is the value providing the aggregate analysis between Lichess and Chess.com? Or is there functionality past what can be found on the respective sites?
Chess.com Insights are similar to what my project is doing. However, Lichess has nothing similar. They do have something called "Chess Insights" but it's not really comparable IMHO.
That said, there are also some unique features like "Openings" which allows you to quickly identify your best/worst openings.
Like the author, I also use regression, but extended to non-title players. More information: https://www.chessmonitor.com/blog/2023-elo-calculation