A number of people have mentioned how EI has big shoes to fill in replacing Tulga.
After talking with a few people in my guild on Order, there was a small consensus that one area where Tulga fell down on was the game Lore of Istaria. Horizons has a nice dynamic world, but when playing that game the NPCs and quests don't do a whole lot to give the world a feel of one with a rich history and diverse cultures.
There are numerous missing races and civilizations that barely get mentioned. Racial conflicts that rarely appear, and few established racial customs. I've seen lore in the forums that the WA has factions, but I've seen nothing about it in-game so far. This and a lot more.
Tulga was great at giving Istaria a future, I hope EI will also work to give Istaria a vibrant past. More storytelling Lore quests and NPCs in the game.
Something to consider making a good name for yourself with.