I was afraid someone would ask that.
I don't have a ton of experience with a bunch of different lenses that fit in my requirements. I have worked up to my bread and butter setup that suits my needs and I have not played around too much. Funny because I consider myself a gear freak in most respects. I want to start hunting for some other options that people are excited about.
Based on that.
1. Canon 135 f/2 (Love everything about this lens more than speed and sharpness)
2. Canon 100-400 f/4.5-5.6 MKI (have not used the Mk II yet, but have been thinking about upgrading)
3. Canon 16-35 f/4
4. Canon 50 f/1.2 (does not focus fast enough for me though, so is a stretch or totally irrelevant here)
The argument started with my love affair of the 135. I am searching for more lenses that made me feel like that one did. I like the 50 f/1.2 but it feels basic. The 135 has a bit of magic to it. I like to shoot large landscapes, small people so I have been interested in trying some wider primes. I love my 135 for details, and environmental portrait stuffs. I shoot a ton of action and lifestyle so I really appreciate fast autofocus, sharpness across a wide focal range. Maybe would like to try something with a bit more richness in color than the 135, but I will probably end up pulling some saturation in post anyway as per my style (I like the flat look of the 135, but would like the flexibility maybe.