All Champions Available to Test in Custom

This might be in the wrong category but...

Which would you prefer Riot do: Keep the way they limit champ availability now, or make it so that you can use any champion you want in a custom game? Keep in mind that even though they're available in customs, you still don't own these champs and you still can't use them in any other game mode. (eg ARAM, ranked, TT, SR, etc)

I'm just curious to see the community's feedback on this idea.