Agreed with codered, people forgot how it was like all thanks to the introduction of stacking weapon combos since the vardan Valley expansion. I would try to keep my argument short as I donno when cinco will delete this thread.

To answer the op questions:
1. Yes I can imagine a mage a rogue a war without the ability to switch between weapons = It means slower and longer party.
2. Break the economy? Only thing I see is people panic sell that may explain the "broken economy" you claimed about because they don't know how their weapons can be used in the expansion map.
3. Changed the playstyle? More like back to how it was supposed to be like.