From a gameplay and game design perspective, my overall impression was that Deus Ex: Invisible War is pretty much in the same game as Deus Ex, just improved in a variety of ways such as better graphics and more streamlined gameplay. That's not necessarily a bad thing in my opinion and I did enjoy the game. However there are numerous minor design issues I feel get in the way of the overall game. I suspect many of the problems are because of 'consolitis' having been developed for the Xbox at the same. In my game, I chose to be a African type male character focusing on stealthy non-lethal gameplay since in most other shooting games, you're forced to play a white Caucasian male that solves every thing by riddling it with bullets.
What I liked:
1) Lots of quests you can take which affects people's dialogue
2) Lots of different, weapons, gadgets and biomods
3) Well written dialogue with good voice acting
4) Game interface and inventory is clean and easy to navigate (very important for a game like this)
1) Maps and areas are very small - This may have something to do with the limitations of the console but everything is a bit too claustrophobic and too small compared to how they would probably be in real life and when compared to the original Deus Ex. This has a rather unfortunate effect of ruining my immersion. It's hard to believe that a busy city could be so tiny. During missions I found myself often having problems finding places to hide if spotted and had to resort to turning invisible.
That being said, I do appreciate the fact that it's easy to get from your main location to where your next mission is compared to the long treks I had to make in a game like Star Wars: Knights of the Old Republic. I wonder if there could be a compromise with this. Maybe have the main areas small and relatively packed with mission areas wide and sprawling? Or perhaps have a vehicle which can get you from point to point easily? Or maybe a teleport system?
2) Linear storyline seems stretched- Despite my initial hope that you would be able to play different areas etc depending on your allegiance, it doesn't really matter whose allegiance you follow in the game. You still end up in the same areas following the same major plotline being asked to do almost the same thing. If you succeed, then you move on to the next major area where the main characters will then ask you to again do something to accomplish their goals which coincidentally means doing something in the same exact location. I was hoping to have some faction specific/exclusive missions that would send me into different areas. A real wasted opportunity.
Also the main quest-givers in the game, i.e. The WTO and The Order and the later two factions seem to be a bit too forgiving to the point of being unrealistic. For example, I chose to side with the WTO early on in the game and The Order still kept trying to convince me to join them and sharing me confidential information on my next target etc. and who I should report too. Considering I had continually disobeyed their orders, I'm quite surprised they were only mildly annoyed rather than ordering my assassination except very near the end.
Also, all factions always seem to know exactly where I was and what I was up to and continuously communicated with me directly. In terms of game design, this was required in order to give me the full variety of choices and missions but in terms of storyline purposes didn't really make sense. It's hard to believe that somebody whose actions they can keep track of so well would be such a major threat to their plans. Again, breaking the immersion. Personally I think they should have design it in a way so that you had to initiate contact with the faction and there would be a faction bar indicating how trusted you were by the faction and whether they would accept you finishing a mission.
3) Faction rewards could be better handled - The game advises you to carefully choose a faction's benefits and advantages but the game doesnt' specifically what benefits you can accrue. I don't recall any particular amazing benefits to be honest. Just a couple of credits, an additional biomod and some minor additional information. I don't know, it just didn't feel different enough. I kind of wanted to for example, be able to call for backup or have access to special faction specific biomods.
4) Non-lethal weapons seem pointless - Like the original Deus Ex, it doesn't seem to be any real reward to non-lethal weapons aside from one or two characters complimenting you and the 'feel good factor'. This time round however, at least the non-lethal weapons seem relatively on par with the normal weapons and you can actually stop people fairly easily with them compared to the first game.
Also I discovered a bug where characters who were unconscious regain consciousness when you re-enter a map and then started fighting allies who have entered the scene to secure the area.
5) AI isn't very smart - AI is okay but unfortunately the AI just doesn't seem to work in pairs or groups very well and is almost suicidal which unfortunately tends to affect the game dialogue. For example, the AI often run into grenades their comrades have thrown and failing to take cover when I shoot them. Overall the environments also don't lend themselves well to any real tactical options.
Overall, storyline is good, gameplay is solid even if areas are a bit small. Factions and faction specific benefits could have been handled better. Won't be a game-changer but if you liked Deus Ex, the sequel is still very much an enjoyable story-driven RPG/action hybrid. I'm not sure why people don't like it. It's not ground breaking as the first game and there are some odd design choices at times but nothing too terrible that would make me hate the entire game like other people seem to do.