Chess Club Ladder App

I am thinking about developing a web app for local or online chess clubs to use. A simple interface where each player has a login, each team has an admin. Below are the rules for the ladder, does this seem fair?

Is there a standard ladder system I'm unaware off?

What other features would be useful?

LADDER RULES

Everyone has access to the ladder.

Each player is 5 placement matches where they play 5 other random players, they get a score at the end of the placements (-1=loss, 0.5=draw, +1=win). This decides the initial rankings, tiebreakers decided as neccessary. Players who join the club after initial placements are placed at the bottom of the ladder. 

You may challenge anyone who is one, two or three spots above you on the ladder.  If you are challenged to a ladder game, you get a notification which you must accept, failure to accept is treated as a loss. If the challened player is in a game, the challenge is added to a waitlist, they must play the first challenge on the waitlist after they have finished their current game. 

Players cannot challenge other unless their waitlist is empty.  

The player making the challenge plays White.  The person being challenged plays Black.

If the lower-ranked player wins, the lower-ranked player takes the higher-ranked player’s spot on the ladder, and the higher-ranked player moves down one spot.

If the higher-ranked player wins, there is no change in the players’ rankings.

If the game ends in a draw, the lower-ranked player takes the spot just below the higher-ranked player.

After a ladder game is played, at least one of the players must play a ladder game against someone else before they are allowed to play each other again.

 Inspired by https://www.chess.com/forum/view/scholastic-chess/chess-ladder-rules?page=1