I couldn't agree with you more. D2, D3, PoE, and any other economy based games like this are not fun. It is an illusion of fun. Took the words right out of my mouth. I believe the entire genre is a complete joke because of trading and awful drop rates. PoE just makes it even worse by having a horrible trading system. At least D3 had an AH you could use to make it as painless as possible. The gameplay itself is awful in these games. It's about as braindead as it gets. But they do what they do so well with their reward systems that it keeps you holding down the right mouse button for hours. It's hard to believe how sucked in people become over games that offer no real susbstance at all (obviously myself included).
I vow to never play another game of this genre again.
Denial you say? You've got a long history of playing the fuck out of this game and then shitting all over it once you've realized you're an addict.
The weakness at the beginning and build-up of power over time is exactly in line with other games of the genre that inspired much of PoE; it's part of the "adventure" element of these games, especially if you're starting from scratch. The main advantages to D3's system are that there is very little collision and you can perform a lot of actions while moving (i.e. Warcry vs Enduring Cry); both make the combat much smoother and arcade-like. D3 also has very few doorways, however, and is mostly just some uninteresting corridors (A4 is literally just a bunch of platforms), so there was a price to pay for reducing the collision. I like both games though, and find the action satisfying in both.