For my, this video does a great job summing up where the game goes wrong
The potential for such a specacular game was there but it never came close to that expectation. A year after its release, I still find myself coming up with alternate ideas a how the game could have been improved, some of which are inspired by that video. I wasn't even too bothered about the DLC (I got From Ashes and Leviathan). Ignore the price/implmentation, the concept behind content in the DLC is really good (especially the identity theft arc in Citadel) but it doesn't tie into the main game enough for me. I would have gladily waited 2 or 3 years to have go the game that could have been delivered.
Here are two examples of how choices could have been implemnted more effectively
1) Ability to direct your War Assets throguh the campaign. This could have opened up more side-missions (not the scanning ones) and allowed a greater oppourtunity to see the fruits of your labour. The missions outcomes would depend on what War Assets youchoose to use in said missions ie Reapers forced to retreat or conquer the planet and destroy some of your Assets
2) More effective use of Cereberus characters, and their actions/fate influenced by your choices. There were only 2 key Cerberus characters: Illusive Man, Kai Leng. A third is introduced in the Citadel DLC, while 2 others potentially important only feature in a single mission. Prior to ME3, I'd thought Mirand's loyalty outcome in ME2 might have affected who she supported in the game. Would have liked to have seen that, plus the oppourtunity to have Kai Leng killed on the Citadel and then replaced another Cerberus commando who is less of a threat (thereby rewarding your choices in the series).
Unfortunately, I can only dream about concepts like this.
