1) Why wouldn't they? Correct me if I'm wrong, but let's take the example of Dexterity and Cunning.
Dexterity, if I recall correctly, increases one's critical chance. Cunning increases one's critical damage. Let's say one has an ability that causes one to do two fast strikes with double chance of a critical hit. Now, with gear promoting high dexterity this means that a critical hit is almost assured with the ability. However, with high cunning it will do more damage. Two situational deployments of the same ability in different situations with different stats and gear. Derp.
First, your initial example was with regards to switching out daggers with a bow. This would require a respec of abilities, not just gear... Which, as i said, would be just like Origins/2. The rest really doesn't have much bearing(though it should be pointed out that in Origins, Dex affected defense, while in 2 it was cunning. That alone would probably affect a build using armor alone).
2) Yes, there is. Generally no more than a +10 increase. Here we have +36 increases or more. Larger swings means more variation - if you have more points on a line, you have more points one can stand on. DAI beats DAO/2 again.
I agree that one can see larger increases in gear bonuses in Inquisition, but I've only seen the +(insert big number) increases on weapons/armor in the crafting menu... We haven't seen very many stats on weapons/armor being picked up off the ground...
3) I have no idea what you're trying to say here. Why does the crafting upset you? Why is this bad for a single player game? I'd feel more confident if you could explain yourself.
I'm bothered by the fact that the focus on gear being the sole benefactor of attribute points forces the crafting system on the player. Something that has been said to be 100% optional. It's not optional if I have to craft an armor/weapon in order to beat an area. Sure, there may be enough drops in the game to get through and beat the game, but at the moment I'm skeptical because we haven't seen anyone pick up any loot during a gameplay trailer(barring the scripted ones like the Avaar boss, and the mage gear in the E3 demonstration).
As for the single-player comment. I was discussing the need for the attribute point display to begin with. There are very few games(let alone RPGs) that display the attributes of the characters and don't allow you to choose the allocation of those points. Usually the game just forgoes showing the player the attributes to begin with. And so I understand why people are upset about the loss of choice in how to allocate the attributes, even if I don't really care about that aspect... But from the other side, I have yet to see it adequately explained why the change is a good thing for single-player purposes. I would understand if it were a Mutli-player game, because you'd want things balanced, but it doesn't make sense to me why they'd change it for single player games, and still show the numbers. But if a player can't choose to not give Cassandra 30 strength at level 10, why even let them see that she has 30 strength?