Also the defense fighting style for fighters is worse not worth taking with 2 handed weapons. You do as much damage with a 1 handed weapon & the duellist style & can use a shield for +2 AC instead of +1. This is a very minor "trap" - 2 handed swords do fractionally more damage & at some point you could have defence & great weapon fighting. It's not optimal but its fine if you want that style I guess.
The issue I have with it is that the starting great weapon PC takes this style. Mind you great weapon fighting is pretty poor too (only <+1 damage cf +2 for duellists).
This sort of thing irks me as it shows a level of mathematical naivety that feels inexcusable but it's minor stuff really.
Assume 3 for Str damage:
7.5 damage, +3 AC: Defense and One Handed Weapon
9.5 damage, +2 AC: Dueling
10 damage, +1 AC: Defense and Two Handed Weapon (one of the fighters in the starter set)
~11 damage, +0 AC: Great Weapon Fighting Two Handed Weapon
13 damage, +0 AC: Two-Weapon Fighting
The difference between Dueling and Defense with 2 Handed is small. However, Great Weapons nova more. 25% of rolling a 7 or higher on a 1 handed weapon, 50% with a Greataxe, and 58.3% with a Greatsword. Sure, the two handed weapon will average just a bit more damage than Dueling, but it will also drop a foe more often. Plus, the +1 AC for Dueling will only help one encounter in 3 to 5. I suspect that the WotC guys know more about math than they did in 4E.
And while it is true that the Two-Weapon Fighting guy wins out at level one, at level five it's a different story (not taking into account magical weapons, criticals, etc.).
15 damage, +3 AC: Defense and One Handed Weapon
19 damage, +2 AC: Dueling
20 damage, +1 AC: Defense and Two Handed Weapon
~22 damage, +0 AC: Great Weapon Fighting Two Handed Weapon
19.5 damage, +0 AC: Two-Weapon Fighting
At higher levels like 11, the two-weapon fighting guy starts falling further behind. But, the Fighter learns new styles by then (level 10).
But sword and board is perfectly reasonable. 5E is deadly. Keeping the Fighter up so that the rest of the team wipes out the opposition (like the Rogue shooting a bow and getting sneak attack damage against the Fighter's foe) is perfectly reasonable.
The Fighter does not have to be the striker. He could be the tank.