This all seems to be somewhat against what I have read.
First. several mods have posted that, yes nothing from verizon comes preloaded on the phone. But as soon as you put the vzw sin card in the phone updates and pushed (in this case we assume go90, my verizon and vzw message). So even if you get the phone via google, the same result. I bet that even the phones from verizon will arrive without those apps, until you activate the sim.
Second it has also been said and confirmed that all updates for the pixel will be pushed out at the same time. I don't believe you will see any delay. But what may happen is that behind the scenes after google is done, verizon may drag there feet delaying the update, then in a unified front you will see the update get pushed. So for example if this was a nexus device, and the update is done on 1-1-2017, then the update is pushed in 1-1-17. but now with verizon, it may go to them and be pushed back to 2-2-17. we wouldnt know because they will push out the unified update in 2-2-17.
I get the bootloader/rooting/roms part. The verizon verzion will not have this ability and if you are one to do this then the only recourse is unlocked. But what if google decided to nullify this by releasing all updates first thru the pixel. I assume the benifit of rooting/roming is to be able to flash it ahead of the update. but what if that didnt happen. I am sure flashiing for some people will have further benefits but that may no longer be one of them.