They wanted to go for a lighter tone after the three games of "The reapahs are gunna kill us all!!!!" The wooden smiles don't sell the dialogue enough that's for sure. Liam had some good development in his loyalty mission.
Drack is up there with the best of the best ME squadmates. His loyalty mission is great. Some of them are top tier and all of them are better that the worst of the trilogy like Kaidan, Ashley, Vega, Jacob and real doll EDI (ME2 EDI ruled).
Dude Ryder flirted with him a bit and I was pretty close to letting Reyes blow Ryder. It's 2819 or something so why not?