I do not think the fight itself was poorly designed bit it did hit the cadets' weakness hard. Main reason why I made Regina the way she is is because there was a lack of ranged capability so that could have made up for that since she is literally the ranged glass cannon.

I will say though that the princess's plan from a regular military standpoint wouldn't ever have been a Plan A due to its chances of failing outright to be extremely high without supplement of some kind and even has a greater risk if injury than Regina's. However, this is also based on anime so all of that can be overlooked and even explained in some form.  

I will say though that in any military RP I get the most enjoyment from when plans go wrong and the characters figure out how to deal with it. But that's just personal taste. That's my two cents.