@krista personally, I am against. Remember that Android is not Windows. If 1 click on the tab in Opera Windows scrolls the page up (and the second one to the previous place) then personally I would prefer that a double click would scroll the page down.
The reason there is currently no "Opera browser for IOS" (to correspond to the full name of the Android version) is that Apple does not allow alternative rendering engines on the app store. That is, Opera Touch for IOS is required to actually have Safari render the web content, the differences between Touch and the native version of Safari being the user interface and My Flow. I'm sure they could do an IOS browser that syncs to Opera desktop versions and is closer to the interface used on Android, but other features of the Android version couldn't be implemented on IOS.
When you go to Yandex, or Amazon, or Ebay... there is a search box you type what you want to type. If you long press that box, Opera pops up an option for you to create a search engine using that box. You can add Yandex as a search by that way.