I did a very similar playthrough actually.
Spacer background, I imagine this Shepard as a wide-eyed privileged brat like Jenkins at the start of his military career, then I chose Sole Survivor as reputation, which hardened him and made him into the N7 Spectre killing machine he became at the start of ME1.
Mostly paragon, good moral compass because he was raised right, but definitely more of a pragmatist on big issues.
Suicide mission goes flawlessly, it gives him hope, but he's in for a tough wake up call.
Miranda, Samara, Kelly, Thane, Mordin, Legion, Ashley, Kaidan, Cortez, EDI, Wrex, Zaeed, Javik (Touched the Shard)
It was depressing, but definitely raised the stakes compared to saving everyone all the time.