I wish I never tried i3. Kept watching all those good looking shots in /r/unixporn, so here I am now: merged between the smooth workflow of i3 and it's extensive use of keyboard, against its shortcomings when it comes to getting my work done as I remembered from Gnome. So I find myself switching from one to the other depending on the day.
When it's time to handle multiple concurrent requests from work, I need Gnome. My response time on i3 isn't yet the best, so that's getting in the way too. However the most problematic thing for me on i3 is window minimizing/hiding (the lack of). Typically there's the need to have multiple custom applications open all the time. Those apps in turn create new windows when required. In Gnome fashion, I let them all exist, and keep minimize, and alt+tab to them when needed.
However, i3's philosophy clearly does not support this way of using your computer, and it tries to work around it by using multiple workspaces (where you can dump open windows when needed). What happens though is that you can lose track of where things are. And if you have a lot of open long-running windows, you might start running out of workspaces...
There is also the scratchpad. A special workspace that can host whatever count of windows you like, and cycle them with a keypress. However, I can't find (or there isn't) a way to restore one of the windows there to a workspace.
Why people find that minimizing is not the "correct" way, I don't know. Maybe the solution is Gnome with i3 as it's window manager. (Or better suited openbox). Perhaps if I continue to use it I'll get it eventually. For now, I'll use it on weekends :-)