In order for there to be a stategy, there has to be an advantage at some point to using a specific command. In a fight in real life, when someone attacks, they've made a commitment to that action. If the attack doesn't connect the way they hope, they are vulnerable during and slightly after the attack depending on how fast they can recover their own momentum.
Like a boxer throwing a huge roundhouse at their opponents head: a very big commitment. If the opponent ducks it, the attacker's body on the side of the attack is very exposed for a body shot of some kind. But if the opponent backs up to dodge it, they may move out of range for their own counter strike. And the attacker still has forward momentum so they could feasibly launch another attack on the retreating opponent.
You might have to have statistics that represent the combatant's speed and recovery time. Plus you may give weight to types of attacks and defense that rob speed and/or recovery time. The benefit may be that an attack that does major damage robs recovery time so the opponent may have two attacks or a defense and an attack chance. But if they get nailed by the big attack, it might be game over!
You can also have defenses that result in attack damage. Or defenses that don't defend an entire attack so that an immediate counter can be initiated that may be equal to 2 attacks.
And you can have people fall if they loose a certain amount of life in a single attack or within the battle itself. They may have to take a turn just getting up which exposes them to another attack - but, in getting up maybe they have the chance to roll so there may be a bit higher potential for the attacker to miss.
So, have statistics like speed and endurance. Obviously two characters of the same abilities will have pretty much the same fight. Maybe slower opponents have more attack power because they tend to be bulkier or maybe they have more endurance.
You can also have an earning system. If a fight is won, a statistic can be improved - but the statistic may also have an opposite. Maybe size is the opposite of speed. So for every 5 speed units, size has to reduced or something. This could help limit the growth of a super warrior and apply strategy where just moving all stats up won't necessarily make the fighter better. I don't know, you can really go anywhere with it.
Enjoy your day.