Ok, I have found a way to do this. Turns out that you need 1 Lab and a custom query. Although the result is not exactly the same.
First you need the Quick Links Google Lab by Dan P.
![Quick Links](https://i.stack.imgur.com/VdvRV.jpg)
Once you have the lab enabled, you can go ahead and click on the advanced search button:
![adv search](https://i.stack.imgur.com/0XTC5.jpg)
Which will allow you to create a custom query (albeit way more limited than Apple's Mail, at least you will have some control).
I select Inbox (not interested in archived stuff or deleted or anything like that), then select (for this example) 1 week from Today. And press the blue magnifying glass to perform the search.
![popup](https://i.stack.imgur.com/5aqQG.jpg)
After you see the results, click the Add Quick Link from the lab, as seen in the following image:
![addlink](https://i.stack.imgur.com/l2h0N.jpg)
This will create a dynamic shortcut that will always point to "the last week" instead of fixed dates.
By using other dates and/or combinations you can create the "sense" of Smart Folders to always have a one click filter for your Family emails, and such.
Best Answer
"Smart Compose" is found on the "General" tab under Settings.
Do note, however, that it isn't rolled out everywhere, and if you're in a country and/or using a language that isn't yet supported, I don't expect that it will appear for you.