We have all seen the issues with fair matching in Alliance Wars. The developers have tried multiple algorithms, and all have been flawed, for multiple reasons.
Trophy scores are too easy to manipulate
Titan score doesn’t really have anything to do with war
Top 5 heroes doesn’t account for bench depth
Top 30 heroes penalizes players who have lots of unleveled 4* and 5* heroes.
The current system of matching, a weighted sum of top 30 heroes, with extra weight given to the top 5, is getting closer, but the basic premise is flawed. The utility and combat effectiveness of different heroes with comparable power rankings varies wildly. An unleveled 5* generally will be similar in power ranking to a maxed 3*, but the 3* will hit harder, defend better, and have more health.
I propose a new formula for determining hero power.
Take the average of the Attack, Defense, and Health scores. Multiply it by a factor related to ascension chevrons. First ascension = 70%, 2nd ascension = 80%, 3rd ascension = 90%, and 4th ascension = 100%
So for example, a maxed 3* with A 500, D 500 H 650 would have a score of
(500+500+650)/3 x 90% = 495 power
A 5* 1st ascension with the same stats would have a power ranking of
(500+500+650)/3 x 70% = 385
When that same 5* reaches 4th ascension, let’s say the stats have gone up to A600 D600 H900 (just to keep the math easy). Power level at that point would be
(600+600+900)/3 x 100% = 700
In this manner, higher ratings would be given to leveled and ascended heroes to better reflect their increased effectiveness