There is logic behind
most these decisions, actually.
Why is a random unique mob one shotting people and takes twice as much effort to kill then a boss fight?
Storyline based mobs always fight the same way every time, so you can get the pattern down too easily for the kind of rewards they supposedly give out. Giving randomly generated rare mobs increased difficulty and payout also makes life a LOT more difficult for botters because they can't do everything on an established path with the same level of success. This also encourages people to play other parts of the game aside from the boss fights, thus giving them relevance.
And not every unique mob is going to be a wrecking ball... just some of them. You are required to kill up to five for stacks of nephalem valor by level 60, so they can't be pushovers.
Why do I need to identify rare items when there are no longer identify scrolls? Seems kind of pointless.
It is. I blame this on indecision during development. I imagine it will be patched out eventually.
Why is crafting completely random? I can craft the same item 20 times and never craft a piece that my character can use...But hey, I'm rich now because I can sell all that crap on an auction house...yay.
There is a VERY important reason for this.... its called gold sink. Crafting costs gold that simply disappears from the game rather than trading hands. When you don't have enough gold sinks that make money vanish, the economy becomes flooded with gold and it becomes nearly impossible for newer players to attain anything later on.
Crafting is also done in a random fashion because if it was done in a static manner it would destroy the entire chance-based architecture of the equipment game.
Think about it... If you have static equipment that is always great coming out of the crafting system, why bother with hunting for uniques or browsing the auction house?
On the contrary, if the crafted equipment is always worse than uniques, why bother leveling up your crafter? You could spend a smaller amount of money on the AH and have vastly superior equipment. The only way to equalize this and make it worth the trouble is to guarantee the production of a unique with a certain number of stats, but within those stats make everything as random as possible. This adds the convenience of not having to do additional hunting for something to drop, but keeps the gambling intact for most of the stats.
Why is there no stat allotment?
More than enough ways to alter your stats with equipment, gems, and skills. I imagine somewhere along the line one of the developers felt that it was just becoming convoluted. The problem with leveling-based stat allotment is that you become locked into your choices semi-permanently in most games with no opportunity to switch things up later on. Clearly they wanted players to be able to play however they wanted to as they progressed, but they also added benefits by level 60 for sticking to your chosen skills.
For example, Nephalem valor stacks up to 5 times and will stay for 30 minutes or until another unique is killed. Each stack increases magic/gold find by 15%. If you change your skills at any point, you lose all of these stacks. The game therefore rewards you for taking a specific skillset and sticking with it from the start of a game, but gives you flexibility of changing things up next time around.
Why does my level 10 gear look exactly like my level 50 gear? Last I checked this is a loot base game...
My level 60 gear looks unique to anything I've worn thus far, but there was a good deal of what you're talking about at the lower end of things. The game was built around Inferno being the end game, and hysterically less than 2% of the playerbase have reached it yet apparently. but hey, they'll get there. It's pretty fun if not annoying at times.