One advantage of charging ,however, is that it might stop the many experts and above who only ever play easy races. Especially if you could find some way of linking the scoring with the difficulty rating.
i have suggested ways to fix the scoring system seen in the suggestions threads.
pros spend endless hours playing easy puzzles to keep there data processing optimized its not that they cannot complete harder puzzles,
easy,medium:
are the standard type of puzzles found in the international competitions they attend in person, {why practices skills not needed?}.
if you want to avoid them move into harder categories ie. hard / very hard there more of a challenge for the fun player.
a large number of the international players play on many different sites that offer similar/same things and are
free, its not going to cost them anything to keep playing.
you do have to realize that a lot of the people that play this game are here to practice for the next competition forcing them away will drop the game played count exponentially.
thus your left with a handful of people that like to play for fun, and very few will pay for puzzles or the options of playing with others when there is other sites that have free accounts with no limits.
free puzzles are easy to find and make on your own with any of the available software online.
to me making it a pay site will delve this site under, there is not a lot of money directly in this game from a consumer at home with a computer and access to options of free.
books etc sell for many good reason a lot of them are because you are not near a computer!
is there no way to find a free serving host?
add in more advertisement to help with costs?
volunteer moderators?