I played insanity on my second play-through; however, I did not use the "new game +" feature. The reason being is that if you import your ME1 character and start a second game you will still get the long-service medal and all the perks of "new-game +" but you will start at level 3 (or maybe 5) and not 30, and because your enemies are locked to your level the game won't start with you getting jacked by level 30 mechs. The only other difference is that you won't keep any weapons from your first play-through, but I did not find them to be a huge advantage anyway because they are not upgraded, plus I played as a soldier and had the Firepower DLC so I had access to the strongest AR in the game from the get-go.

Playing as a soldier Shepard, I made sure to pick Warp Ammo as my bonus power. Some guides I read have suggested the Geth-Shield boost or Fortification. In hind sight  I may have picked one of those because it could have been very useful in the early levels, and the Warp Ammo is not really necessary until Horizon and you have the opportunity to retrain powers before then. That way, early in the game when you are weak and have no upgrades you have some additional protection and later in the game when you need the extra killing-power you switch to the Warp Ammo. The reason I picked warp-ammo over any other offensive bonus power is that it seems to be built for killing collectors, giving you bonus damage against barriers, armor and health.

I was actually surprised at how quickly I got used to the new difficulty. Mass Effect kind of has a reversed difficulty curve, in that if you make sure you get upgrades quickly the game seems to get easier as you go on. My squads usually consisted of whoever I felt like brining unless I felt that I needed specific abilities, for example, on missions where I would be fighting collectors I would bring Miranda and Thane because I could use Warp to take down barriers and armor, on missions where I would be fighting a lot of Blue Suns I would bring Miranda and Garrus so I could Overpower shields and so on. In battle I would turn Squad Disruptor Ammo on for the team and then typically switch to Heavy Warp Ammo for myself, so the squad could take down shielded opponents and I could finish off everything else. The only other tip I can offer is make sure you pick up Hardened Adrenaline Rush, as it can keep you alive long enough to get that last head-shot on a heavy mech and don't be afraid to just sit behind cover while it recharges, Insanity favors are more methodical play style.

I am not a guy that usually looks for a challenge in a video-game, I just want to have an experience, I originally started the Insanity run just in case there are any bonuses for doing so in ME3. But now that I am finished I am glad I did it just for the sake of getting an S-rank in what is my favorite game of this generation, possibly of all time. 

Have fun, kids!

Fait622