It's not missing anymore, I found it in Routing->Rules, I'm pretty sure you'll find it there too.
As for quick filter that was in v6, it would be nice to have it back. Yes, it was duplicate functionality, but also very handy shortcut, because you had always visible dropdown, where you could select routing table you're interested in. You can get the same result using filter, but for that you have to click filter button, select "Routing Table" from long dropdown, select "is" from another, select routing table from third, and finally click "Filter". It takes too long.