Riot, Please Add a Tab to Let me Try On Items

One thing I would like to have is a character pane, where I can toggle items on/off and see my stats as they would appear in game. I understand that all of this can be calculated manually, but without doing much work, we could try out various build paths, and see the results in real-time such as, our health, attack speed, cool-down reduction, etc. This would also be a great feature because currently the client does not have a way to browse items outside of being in an actual game. This would be such a great way for the community to get a feel for new items, or ones that were nerfed/buffed or a basic understanding of a new champion.

Maybe even down the road, Riot could even include features to show what your stats would be if you had baron, or if you had 'X' dragon kills, or any buffs at all.

Note: I tried searching for this topic through a myriad of different key words, and couldn't find anything. I apologize if it's nothing new, and has been discussed in the past, but I haven't seen it recently.