I preferred Welbeck as a left winger in the old system - I really rate him there actually. As the main guy up front he just doesn't have the goals in him. His pressing, movement and ball carrying is something we sorely miss when Giroud plays up there in my opinion.
The thing is with Giroud, I want him to stay and play off the bench behind a newly bought striker, but I don't really ever want him to start! I just don't like the way we play with him as the focus of our attack. That's obviously not realistic, especially in a World Cup year.
We'll have to see what happens on the new striker front first.