to win with the elves is not very difficult. They have the influence superority and the combo archer - darnari warrior (archer turns the fortresses up and danari elminates enemy unit a few seconds later.) Addtional they can reach for cities and powerful monsters much sooner than other races.
Yes, but there are a few problems with the Elves. The first is that they need to buy their 5-gold unit to get card draw. Otherwise, they have trouble getting enough units in one turn.
Second, if you play a Darnati Warrior first, he's vulnerable to getting taken out, so it's often better to sacrifice a Deepwood Archer first. Also, you can't use the Darnati Warrior ability first if you're starting the siege.
Third, they can get some neutral cards sooner with the Storm Sorceress, but they struggle to get enough attack to take the cities before the other races.
And fourth, even if they get cities, you can cripple them by laying siege to their city and stealing it from them. The only times I see the Latari Elves win is when they are left alone for the first half of the game and can build up an army. I find that Waiqar and the Uthuk Y'llan are much more capable at taking cities early on.
These are all just my opinions based on my experiences and are not "fact", so feel free to disagree.