In the past year or so of Diablo III being out I have played around One Thousand hours. Each update from 1.0.3-1.0.8 has brought new feats and faults to the current game. Though I enjoy Diablo III as it is currently on the single players side; If you play multiplayer self finding without the auction house the game has quite a few more issues.

This being said; It was made as a solely online game which makes the game a multi-player preferable game, though the single player play is better as a whole.
Currently the Diablo III Auction house has been made into a game of flipping while trying to avoid Auction House Bots, as well as paying to win a game that is made as a grind. Though I understand Blizzard needs to make money off of the auction house to keep servers up and running; With the current rate of inflation, though inevitable the multi-player aspect of the game is going down the drain.

In soft-core there is to many items, and to much gold coming into the game to keep a healthy economy. If pvp was brought out where if you die you lose your gear this would help keep a better economy. Top tier gear would be taken out of the game in turn creating a healthier economy, and people would defiantly continue to do pvp for a chance at being a top pvper.

Diablo for me has always been about the thrill of the progressive grind.

-Currently I am at a Dps Check on my wizard (305k unbuffed), I haven't been able to find an upgrade for my non-craftables in over 200 hours, that keeps my survivability at a reasonable level.

-The auction house has been inflated to the point where I can't collect enough gold/items that sell to pay for the 800m-5b item upgrades I need to progress to the next tier of players.

-Often if your trying to farm in public games you have to deal with people playing on Mp's they shouldn't be playing on.
I enjoy the grind of Diablo but if Blizzard could work on some sort of like Gear/Dps/Resistance check to play on a certain Monster Power that would be amazing.

I have been reading a lot of forum posts recently about ideas to progress Diablo III as a game, here are my ideas/add-ons:

1.) People often get tired of Diablo because your repeating the same run to get through the biggest mobs highest density of elites for the most experience, DE, and legendaries per hour. If there was a new sort of dungeon introduced. such as a dungeon with a progressive ladder of difficulty; Harder white mobs and harder elite, eventually getting to bosses that had higher drop rates it could create a fun new game type.

2.) I also thought that doing a variation of mp10 would be fun if you could be rewarded something like a guaranteed some of gold or Legendary if you fortified a piece of armor or weapon for a whole run having to clear a particular area.

3.) Finally playing games such as Farcry 3 reminds me of how much the bounty hunting aspect in some games is fun. If in Diablo III there was a particular random spawning character some place in the act and always different and you had to hunt this and kill it to turn in a reward such as (gold,large amounts of XP, or a random Legendary) this could possibly be a fun and interesting add to the game.

This game is great, If the blizzard staff keeps making improvements and asking for feedback from the public the game will hopefully progress to a healthier and more sustainable game. I hope that everyone will tell me how they feel about my ideas; I love feedback!