its worth coming back, the game is very much worth playing, especially if you havent in over a year. you are going to be have to the type to make your parties and shout.
i get lot of feedback on how they seem overwhelmed, especially if they had some standing prior to leaving. you will feel like you are playing catch up. however if you are the type to get ***done on your own and are practical on the jobs you play/come on, there will be tons for you to do, it will almost be a new game.
my advice to you is start with daily farming of gil and currency with your bst while you assimilate.
focus on bow for your rng-sam
start with getting homepoints and waypoints
http://wiki.bluegartr.com/bg/Home_Point
while working on records of eminence
http://wiki.bluegartr.com/bg/Records_of_Eminence
buy a decent weapons for your bst rng sam blm smn
get the basic armor set from there as well,
catch on any wildkeeper shouts, this should force you to nagivate all the zone and meet many basic requires for KIs
http://wiki.bluegartr.com/bg/Reive
do the quest order up for decent bst weapons.
do the quests for KIs to navigate these new soa areas example climbing,rafting, reivy unity logging etc,
once you get to yorcia spam skirmish on your blm or better yet just whm, start getting your otronif gear for pdt/mdt sets and start of decent ilevel gear you wont toss.
then start doing skcbcnm 20 for tales to reforge your afs for your rng and sam
then go to AA and delve shouts and kill tojil, 20+ times to update your plasm and tales 6-10.
at that point you should at least be on your feet. should take 3 weeks or so.
if you need a linkshell let me know.