League of Legends: Owning Champions

At the start of any draft match in League of Legends each team gets to ban 3 champions. Those champions can't be chosen by anyone on either team in the upcoming draft. On top of that any champion can only be drafted once. This means you need to have access to at least 16 champions before you're allowed to play. (If you're the last pick it's theoretically possible that the 6 bans and 9 previous selections will cover off 15 champions you own. If you only owned 15 or fewer champions you'd have no one left to pick!)

One thing that isn't explicitly stated anywhere and which confused me the first few times I had to ban is you aren't given a selection of every hero in the game to ban. (My team told me to ban Morgana and I freaked out when I couldn't find her on the list.) You're actually only allowed to ban a hero which is owned by the other team. So if Morgana isn't in the list it means the other team is actually incapable of choosing her. That would mean you'd waste your ban if you used it on Morgana and it's actually pretty awesome that the game prevents that from happening.

This feature actually has a few consequences. If you're paying attention and notice that the other team doesn't have a popular hero (like Rammus for example) you can't ban him. But that knowledge also means you don't need to draft him highly either! You can guarantee that he'll still be around at the end of the draft (assuming they don't use one of their bans on him) and use your early picks on actually contested champions. It's also possible if you see the enemy team has very restricted choices for a role (perhaps they only have 1 or 2 of the healer champions) you could use your bans on those champions and force the opposing team to run with a 'bad' team composition.

This all was really brought to the forefront when we played our first ranked team games on Friday. Some of us have a very restricted number of champions and as a team combined we only had 50 champions between us. Our opponents in the match we noticed this had 83. This gives them a lot of information and power if they bother to pay attention to it. It also came to mind that we don't have a lot of ability to trade champions since we don't really own a lot of the same ones either. If I'm picking early I actually can't grab Rammus for Robb to use since I actually don't own her. And even if I did he doesn't own Akali or Nasus so he wouldn't be able to trade a hero back to me for her.

Obviously the solution to both of those problems is for everyone to play more games to earn more currency to buy more champions. But the question I've been asking myself is which problem is better to resolve? If I'm going to blow some points on a champion I'm not likely to use is it better to buy one no one on my team owns (potentially allowing the other team to ban a champion we won't use) or is it better to start building a swapping matrix by buying all the champions the rest of the team wants to use? I think possibly the first step is going to be determining precisely which champions each member of the team owns?

Does anyone have any opinions one way or the other as to which is the best start? My initial feeling is that I should pick up frequently banned champions (Morgana, Kassadin, Shaco, Rammus, Lee Sin, Skarner...) and then work on setting up trades? Ideally if I keep playing the top lane with the team I want to have my selection happen last in order to counter whatever champion they pick so being able to trade properly with the last pick player would be optimal. (But we couldn't figure out why it was ordering us the way it was so I don't know if that's even feasible to figure out.)