There is a tutorial... single player
You play like 8-10 matches... I forget. Each one is a differet game type, but each game type forces you to use different skill sets with your character.
one game type you need to destroy buildings, so you invest in building destroying spells
another is about holding flags, so you learn about locks, and capturing flags
another is about killing enemy dg so you learn about your burst / damage capabilities.
and so on..
The pace of the game is slow and you have time to read each item when shopping and decide if you want to buy it or not.
As far as an "unranked" option, that's what customs games should have been while having ladders and match making for various other game types. It also makes it easier for you or a friend to try a new build or play a game and make your own rules like "stupid items only etc." and mess around without it having to count