Guild Wars 2

In order to encourage players to bring out their minis, I suggest this:

Do not need to have minis in our bag to activate them

During player log in, they can choose which mini they want to go adventure with the duration of minis existing beside players will have a limited time frame, let use 30 minutes, this then creates a cycle. that renews at a X hours time frame.

Player can also choose not to have mini with them.
or
We can choose to put them on rotation, every time we log in one of our mini in the bank will automatically show up and the next one the next cycle.

Explanation
First batch of players (maximum allow minis per map reached = first batch)- logs in at x hours, their minis last for 30 minutes

Second batch of players will have their minis appears when any of the first batch players log out or their 30 minutes runs out. and so on. activated once every 12 or X hours which ever is suitable.