Practice in League of Legends (A Suggestion!)

Hi! I'm FallenKingTel - I play exclusively on the NA server, and I'm somewhat new to this game. I received my first ranked placement a little earlier than I should have tried to, due to over-anticipation and lack of patience, and placed in S4 at the very end of last season, and this season I'm paying for it by being placed in B4. I've gotten two of my friends to play this game with me - one of whom isn't a very big fan, but still enjoys the experience even if it is (in his opinion) "pay to win." As we're all at least new to League of Legends, though we have a basic understanding of and amount of experience in other MOBA's, we've been trying to look for any way to find what champions fit our play-styles best before we make a commitment into hard-sticking to two roles and a few champions that fit in said roles that we play whom we enjoy. However, this is to no avail, due to the lack of new-Summoner-friendly content in the game (sorry if that seems like a hard hit!). Our issue is that, outside of the free rotation or purchasing a champion, there's absolutely no way whatsoever for us to practice a champion we like or learn new champions in bot matches! I understand the need to make a living over at Riot Games, but bot matches should be a place that new Summoners can go in order to try to learn, even if they don't own the champion they want to learn or practice with. This would, of course, allow Summoners to try a champion to get a basic grasp of their abilities before they frantically and impulsively spend money on them, but in an environment where it has no impact on other people and they don't get flamed for doing bad because they don't quite have a grasp on the mechanics of the champion in question - while this is available every week, you shouldn't have to wait weeks on end to play a champion you don't know anything about against bots. In conclusion, I propose to you and the League of Legends community that the full range of champions be added to custom games (where you don't earn any mastery or IP) and/or co-operational games against the AI. Thank you for your time and consideration.