I don't think you will any advantages, uness you shoot sports or birds, etc. It is a fast action camera. A few years ago, I was thinking of getting one. I went to a local store, checked out the 60D and 7D and walked out with the 60D. You need to try one in a store, if possible, and see if you like the complexity, size and weight of the 7D.
It is a very sophisticated camera, but I doubt if there is going to be much in the way of a difference in the images, if you are shooting portraits or architecture.
You might find that you prefer your T3i. It has the articulating screen, and is light and compact.
The 7D does bring at least one major advantage to the table as regards general photography that the T3i doesn't have: spot focusing. I've found that to be invaluable for focusing on exactly what I want.
It helps, too, that it has a gloriously bright and big 100% coverage viewfinder.
The 7D is simply a more capable camera than the T3i. But the T3i certainly has the size and weight advantage. While the 7D's capabilities may be most useful for fast moving objects, don't make the mistake of presuming that those capabilities are useful only for that.
I find that the more capable the camera, the better off you're going to be. You might not use all of the camera's capabilities, but it's almost certain that you'll find some capabilities of the camera, which are not shared by the "less capable" model, to be useful.