I agree with Mykonos here. Personally, I feel that people who buy heroes with ICE are at a disadvantage, because they have not taken the time to accumulate experience in the game. You can't really jump right into Vainglory.

When I was first learning, I ended up buying Ringo, Catherine, and Koshka. That way, I could focus on learning the playstyles for just three characters, and I wouldn't have to worry about them disappearing. Also, I could choose whichever type of character I needed(Lane, Jungle, or Roam) for the specific game I was in. Instalocking, amirite? (: It didn't cost much glory-wise. I personally think this is better, at least at first, than trying to master each new character as it comes...