At least with ME2, Tali and Miranda make interesting choices. Tali was loyal to you from the first game and the attraction was always there from the dialog. After the flotilla her reaction to saving her (and her father's name) leave her in awe and near speechless. It's something that grew over time and I appreciate that. With that said, Miranda is the exact right version of a woman in my opinion. Smart, smartass, yet still very charming. Her attitude is perfect and tends to make the right comments in the right places, she keeps her cool and is deadly [figuratively and literally.] The choice between Tali and Miranda is honestly hard since I actually like the romance options in ME2.
That said I'll go for Garrus with femshep, there's just no question.