Play Any Champion In Custom Match Please think about this

I was thinking that there should be something in custom matches where you can play any champion and use any skin for the champion, if you're saving up for a champion and you want to see how you like them to make sure they're who you really want, this can do it, or if you want to play a champ for fun without using IP then play them in custom, what if you got someone and found out you didn't like them, that would suck, so I think that you should be able to play any champion in Custom matches.