I know this is an old topic but this is sort of a big update.
The game went open beta last week and is completely free to play now. You can buy small upgrades like stash slots, character slots, cosmetics, ... Though with the default game you got more than enough slots and stuff. With the start of the open beta last week also came the final character wipe so that's another big plus.
All those who enjoyed Diablo 2 a lot will most likely enjoy this very much too.