The purpose of the game is simple. Kill mobs, make adena (not by killing mobs) so you can buy better gear and kill mobs faster
1 to 105 is easy, it shouldn't take more than 2 days of auto farming. The quest line ends at 105, take advantage of the free pots that are currently available and get there as fast as you can. While you have the 7 day vitality rune you should also 85-105 your chosen dual class. After 105, there is no quest line and things get progressively harder as the game basically forces you to spend real money to progress. In the old days all you needed was a weapon and armor. Now there are multiple systems (artifacts, forgotten skills, brooch, shirt, circlet etc) all of which pretty much require real money to upgrade
oh and spoilers are now just daggers. Spoiling no longer functions like it used to, you can't really gather materials, sell them etc. You now (from Hellbound mobs and up) get augment stone crystals, which you can trade in for augment stones. That's it.