My Esper can also switch to healing for PvP if needed at certain times. Managed to grind out all of the 1500 rank BG gear on it for both DPS and healing the other night, i just need to rune up the healing set pieces i'll use. With the PvP patch coming in a few weeks it seemed sensible to buy every piece from both sets for when the gear changes come, most of it'll be sitting in the bank till then but at least it's there.
That being said, we really need to start hitting the Arenas before that patch so we can stock up on the 1800 gear, especially those of you who play Engineer and Warrior as the weapons from that make a massive difference in your damage.
Runes, i cant stress how important they are for those of you who will be hitting 50 soon. According to the forums DPS Espers are supposedly gimp yet going from no runes to a full planned out set of them took me from concentrating on using CC to control the objectives in matches to being able to 1v2 and win vs most classes except 1800+ geared warriors that knew what they were doing.
....though I don't have a huge amount of playing time so was thinking of spending maybe 1 hour 3 times a week on it, with maybe a bit more on weekends.
