This "feature" is retarded.
I don't like locking in my champion for the same reason I don't lock in the first ability at lv 1 in the fountain. Heck, I can understand getting penalized if I don't click a champion, but I'm getting penalized because I'm selecting a champion and then not locking in because I'm still strategizing with my teammates over team comp.
It also doesn't help that the client UI is so laggy (even in low spec mode) that even if I notice the timer is low, it takes a couple seconds lock in. It's even worse if I notice the timer while I'm modifying my rune pages.
Also, AFK check, really?!? The accept/decline screen is there as an AFK check. What am I going to do, accept the game and then suddenly go mow the lawn.
Hopefully someone listens to this little rant of mine because I literally (literally literally) just uninstalled the game because I'm so annoyed over how unusable the client is right now. (the game itself is great) Hopefully if/when I get back on the client will be better.