stamina indirectly forces players to buy licenses from the item mall to make the most of their stamina. most of the licenses are very limited and in the long run (adv and merc storage licenses mainly), the item mall is the only place to get them. patrol licenses are required to make the most of your stamina otherwise you can run into a group of mobs without the mob you are looking for.
EDIT:
remember, ndoors said they are not going to add stamina pills to the item mall. this will not stop them from adding other items like stamina regen license, no stamina usage for x number of battles, exp boosts to even out the exp while without stamina. if they don't do anything like this, many of the items in the item mall probably won't sell in large quantities.
lvl 100 in 2 or 3 days is very possible with the item mall and scrolls. that's just how broken the item mall is going to be. atlantica has good intentions, but the items in the item mall heavily sway it in favor of scroll spamming so that you can make the most of your stamina and i don't think they will remove the scrolls in our version. normal players can do this too if they're willing to fork over like 3 mil for an adv scroll and eventually something like 8 mil for a pre scroll. 100k exp for a char in 1 fight is more than what most people will get from 1 fight until lvl 90 probably.



I'd say it's pretty massive. Quite graphical (im running it at 1680x1050 resolution. So I don't really see why you compare it to a browser game.