I disagree. I think the current system works great.
When the "always open" setting conflicts with a current container, you get a prompt. If you want to open a specific container, long press the create tab button to get a selection of containers so you can browse to the website manually.
Using multiple accounts works great for me. Clicking on links will open in the same container, opening the website in a specific container is easy, I don't see the blocker here.
I don't know how many containers you intend on using but I don't find the feature problematic at all. Maybe the Tree Style Tabs integration is fixing a problem I don't know about, but it's working great for me.
When the "always open" setting conflicts with a current container, you get a prompt. If you want to open a specific container, long press the create tab button to get a selection of containers so you can browse to the website manually.
Using multiple accounts works great for me. Clicking on links will open in the same container, opening the website in a specific container is easy, I don't see the blocker here.
I don't know how many containers you intend on using but I don't find the feature problematic at all. Maybe the Tree Style Tabs integration is fixing a problem I don't know about, but it's working great for me.