I don't see the new leaderboard changes anything for the people who can not invest alot of time on graal, since the score is calculated the exact same way. The only thing changed is now they will reward the people who invest the most time on graal. 
It does encourage people to spar, but they will eventually go back to normal as they realize they have to constantly spar alot daily to compete with the people with the most free time. And of course, it still discourage people to start late in the season. The same goes for pk and bk.
As for the all-time leaderboard, put a "first to have 100k pk" just like the spar wins record in the arena library.
At the end, the new update for the leaderboards doesn't really concern me and most of the players. I do want the old GS score system back tho.