What faction is most appealing to new players?

[Tenebrion]

Right now I want to avoid any faction that has any glaring strengths / weaknesses. In other words, I don't want her first faction to be something like EA Abyssia, because they have a exceptionally powerful infantry but no range. Likewise, I wouldn't want her to play a faction like Caelum due to their fragility and high mobility, or Ryleth / Atlantis for obvious reasons.

In other words, I'm thinking the best choice, for a starter faction, is a jack of all trades kind of nation. That way, once she tries the other factions, she can have a better appreciation of their various strengths and weaknesses.