At level 10 you start to feel the need of new gear , in beta they gave new gear with guildleves, now they don’t (all I got is a ring in 6 level 10's so far).
To get the gear you need, you must craft (since there is no AH and bazaar system, it takes so much time) to craft you need materials, these are collected, gathered or sold by vendors, if the material you want is sold by a vendor in a city that you are not in, then you have to travel there (running, ferry), and that’s because there is no mail service for someone to send it to you.
So to progress in this game without (AH, mail system and transportation) you need to level at least 4 crafting jobs and learn all gathering jobs, and you need to be level 15 in these jobs to get level 10 gear.
As much as I love FF games, this game will be very nice when they implement AH, Mail service and chocopo.
Till then, I think ill level everything to level 10 and if that happens before the free 30 days ends, then I'll stop playing and come back when they implement them.