Order of attacks is another aspect of the game related to where your creatures deploy on the field. Specifically for Bone Wall, I often find myself counting out where the charges will run out and if I should Deflag a charge to get my big Golem through in slot 3.
First I'd start by defining the spots better in game, maybe numbering them like Slot 1 for the first (middle) creature, Slot 2 etc and showing the info when you hover over the card.
You could go further and let the player choose where to deploy their creatures, with an extra click to the target Slot. Then you can have positional deployment and formations, or defenses that are strong in the middle but weak on the sides. Give an advantage to Flying creatures in your forward slots, that sort of thing.
You could have something like a Gravity Shield that let only even # creatures attack you for 3 turns.
Someone also created a spell that dealt damage to a creature and all creatures next to it, like a cone of attack or something.
It would add a metric ton of strategic layers to the game if you had to think about where your creatures were deployed.
