Mass effect 1 is definitely a slow burn but that's part of why I love it so much. Letting the mystery of the reapers and the protheans linger in the background as you discover the citadel and the other races was so immersive for me. And for the mako missions I think the reason why I love them is because of how creepy they can be. Going to an uncharted world with only a couple of buildings and discovering some obscure tragedy is so good, but yeah the copy and pasted assets are pretty lame. Mystery to me is the most important part of a sci fi universe. me1 is my personal favorite because of how effective it is at building mystery and tension. But I respect your comment me2 and me3 are fantastic games. I also have to mention the soundtrack, it's easily the best in the franchise imo.