Well, there are only three Grand Tours of which the TDF is one. I like them all. Enjoyed the Veulta the most in 2017 but missed all of the Giro last year.
However I enjoy most any of the tours, grand or not. The AmGen tour of Califonia was also reasonably interesting last year as were the UCI championships.
I lean toward any of the road cycling type endurance events as I somewhat can figure out and understand the various strategies. I enjoy watching some of the mtn bike stuff and bmx stuff like at the x-games which leaves me a bit flabbergasted and amazed at the things they do, but I don't understand it so I don't follow it closely.
I'm pretty much hampered by what I can see on NBCSN or NBC sports gold. As well by the time I watch the stuff on there that interest me, I don't have the time to look for any other cycling broadcast or youtube.