Pro looks great - I've been working with it probably 5% of the time for the last 1+ year- and packs in some great new features that have been missing for too long. But it strikes me that the interface being forced on users is more of a sales pitch suited for casual users trying to make a pretty graphic for a school project or town meeting or something and is not conducive to production work.
The software is laggy.
When editing AGOL attributes it syncs with every edit rather than waiting for me to leave the attributes window to sync.
Basic streamlining tools are missing that aid in editing and review. For example why can't we have an on the fly rotate data frame tool so that I can orient my map to match the plans I'm looking at in the other screen?
Thanks to the ribbon, tools that used to take one click to access can take 3+ clicks and switching between several different ribbon panes. I can't be the only one that craves the customizability of where my tools are and which tools are displayed by default at all times. Stop trying to help me by hiding things you think I don't want!
Get off my lawn!
I'm not usually one to rant, and I know that in part I need to keep getting acclimated to the the flow of Pro, but it's frustrating when ESRI appears to be more concerned with how clean the UI looks (and to be fair developing and adding long overdue new features missing in Desktop) than it is with optimizing functionality for production users and implementing long standing and necessary ArcMap function for all day users.
Am I missing something here with Pro? It just seems new and shiny to me and doesn't hit me as something I'd ever want to use instead of ArcMap exclusively.
(It's worth noting that I remember my old boss complaining in the same way when we had to transition from 3.x to 9.x....he was wrong back then, but I mean come on, surely I'm in the right today)