The idea for PPC-like POS coins is to make a parallel chain. Eventually you'll succeed in winning against the main chain.
Ok, so you're going to buy a loads of coins and then
grow a chain of your own. And once coin operators get a whiff of what you're doing,
they will resort to automated checkpoints and eliminate your fork.
I'm sure it's a nice hobby though.
if checkpoint frequency if faster than standard confirmation times then you don't have POS based consensus, you have centralized bs!