Don’t introduce pay-to-win mechanics that leave your core fans as mere cannon fodder for your metaphorical whales.
They’re simple: don’t segment the player base across multiple DLCs that results in being unable to find a match. You could likely fill a book with truisms that gamers would prefer developers to adhere to statements that ought to be obvious that somehow seem to consistently fall wayside when developers bring new fantastic works to light for players to explore.
