There will be spoilers on the end of the game below.
First, this game is soooo much more difficult than any other game in the series, especially toward the end. The difficulty started off pretty easy, but spiked as I got closer to the end. What made it that way? Those damn Banshees. On one hand, I can appreciate the difficulty because Shepard is fighting to save the galaxy. On the other hand....those damn Banshees! So anyway, it's going to be rough on Insanity. I will have to play as something other than a Vanguard, heh.
On harder difficulties, combos are going to be a necessity. One tip I will throw out there is if you have a choice between Banshees and other enemies...always kill the Banshees first. I learned that the hard way. At one point in the endgame, the enemies did not stop spawning until all the Banshees were dead. I seriously did battle for 15 minutes before I figured this out.
The end of the game was weird. I'm ok with sad endings, and that's what I was expecting. However, I can't understand the very end when Joker is trying to get away from the blast. Where is he going? Now he is stranded on some distant planet with Shep's girfriend with no way to return. Everything else I am ok with, but that was just bizarre. I even watched all 3 of the endings on youtube to see if I was missing something, but no...the same thing happens on each ending. Other than that, really enjoyed the game and I appreciate the depth and scope of the endgame. The reasoning for the "solution" made sense. I hate predictable endings, so this did not disappoint. But after spending countless hours on the series, I am left feeling a bit disappointed that the crew/Shepard didn't get to be together to help rebuild.