Firefox vs Opera

I decided to share my impressions of choosing a browser and ask for advice.

So, I like Fox
! display links ;-)
! Of course, modularity (extensions) - for example, WebDeveloperTools used by me - there is no such thing in Opera, but I would like to
! the correct work with the services from Google (there were troubles at the time at Opera with the display of Gmail, for example, but I generally keep quiet about Google Docs)

Like Opera
usability is something
...! access to the top ten and favorites when attacking the address bar
...! built-in mailer, for example pick up mail from the same Gmail
...! reading feeds (short feed descriptions) in the same browser
...! the ability to easily set up search plug-ins - you just get into the search bar in the right place and click the right button “Create search” (for example, separately by Google pictures, Yandex dictionaries, etc. - only with SearchMash does not work)
...! of course speed

I don’t like Fox’s inability to set up search plugins the way I want - if you know how to do it quickly - please share it ...
')
Not like in Fox also eaten off the amount of memory

And of course, the absence of those convenient amenities that exist in the Opera

In Opera, I don’t like the fact that the widget idea isn’t used to its fullest - there’s no feature set like Fox’s extensions \ although I may not know much \

Do you know how to combine all the goodies "in one bottle" and who chose what for seby why?