I'm making a score system that will be based on several factors, how many collectibles you have obtained, how few hits you have taken, etc. I want to add in a multiplier based on how quickly the player manages to finish the game.
So far the only thing I've thought of is to have a maximum time, and to subtract the final time from that number. So as an example, say I set the maximum number to 300 seconds and somebody beat the game in 220 seconds, that would leave 80. This could be divided into a smaller number and then used as a multiplier on the total score.
It works but feels a little limited. What would be a better way to achieve this?