I'm only 6'3", and that is early in the morning. At night, I'm less. But, like you, I also have a 34" inseam. I have several bikes and an ett of 58cm-59cm seem to fit me quite well. One is a Madone 4.5. The bike is spec'd as a 60cm, but has a 58.6 ett, (I have no idea why they call it a 60cm bike. No measurement on the geometry diagram is close to 60 cm.)
I'm lusting for a Domane, but my burning desire is in check right now.
Just my own opinion ... I wouldn't own Tiagra. 105 is fine. (My Madone came with a mix of 105/Tiagra/no-name; and has been, over time, "converted" to Ultegra.) The worst complaint about the Madone was with the seat and the Tiagra brakes. All the reviews said it has poor stopping power. The seat and brakes were the first two things I swapped out.
The ett of my bikes are: 58.6cm (Madone 4.5, 60cm size), 58.6cm (Kestrel RT800-SL, 59cm size), and 58cm (Pinarello FP6, 57.5 cm size)