Im inclined to consider the differing Strategic Victory levels more of value as it takes in consideration the the entire performance of both sides over the entire length of the battle regardless of the Forces ratio between them, or one side may have far less troops than the other. Where as Tactical can change more quickly based upon a last minute action by one side or the other.
These 2 victory level in my view would be more appropiate in a Campaign. Rather than in a one off battle.
So therefore for a one off battle maybe the 2 levels Strategic and Tactical should taken into consideration.
A true draw of a result would be:
If One side obtained a Strategic Victory of Substantial, and the opposition got a Tactical Substantial Victory then it would be a true draw in my book.
Any change greater than or equal to a result between Tactical or Strategic, would be on a ratio basis and compared to a end of game result for a one off battle. Would be more fair.
This is just a thought I had