A very good example, that also shows that things always have another level that one can look at.Ignore the sheet and ignore the pentagon.
If you do autocombat follow gargons advise.
If you do manual, then use experience, try and learn what works and what doesn't.
Also in which chapter are you? are you writing under a pseudonym? I only see a chapter 2 account under your name and those do not have a spire.
the combat pentagon works best if you are in the very early game and play on manual. this is because special abilities on units are not yet unlocked.
and often the same with attack boosting buildings which you do not yet have or developed. in an early game the with sub par units a 2 wave fight might be very impossible due to the lack of power.
In general it's a game of striking first, the one who deals the first blow wins. this becomes especially prominent when units unlock there special abilities. at that point the ranged unit with the correct ability might outperform "the best unit" just by the fact the can decimate that unit on the initial strike.
The game also alows some units attack to be improved, the stronger the improvement the stronger ranged units become.
My prime example is how I often use blossom mages/priests vs light melee. according to the combat pentagon thats the dumbest move ever.
But because these units have a special power that destroy defence and have a range of 5 they can strike first AND stay out of harms way.
The first hit does limited damage but the next unit does a massive amount of damage because you just destroyed his defence.
So my favorite units agains thieves are 5 range mage units.
This is something you can only learn by ignoring the combat triangle, look at each units strategic strength and weakness and then experiment to test you theories.
For this reason it's a shame you cannot do manual combat on the app, starting with manual combat makes it a lot easier to learn as you can asses the result based on you expectation and external factors like map layout somthing you cannot see with autocombat.
A strange result is often the result of map barriers, but how can he diagnose and learn from this odd result if you do not know of additional factors outside the combat pentagon?
What is true for the 5 thieves (range 5 mages are best) is less true for 5 Ancient Orcs (still Mages can kill a lot of them, but they cannot stay out of range anymore) and is a horrible idea if facing 5 dogs (no damage and nearly guaranteed to get massacred after the first hit). All of the enemies are LM units you can face in the tourneys, but what works best against them is very different. The pentagon is unfortunately not much use in figuring this out.
As a first step in your trial and error path to fighting, the pentagon is quite useful. But as @CrazyWizard has said, the App is an extremely bad teacher and I would say it is nearly impossible to become good at fighting if one has no access to a browser at all. For learning the browser is nearly a must. Once you know how it works it is easy enough to go back to do the actual bulk of fighting on the App. It is much faster there I do between 90%-100% of my fighting every week in the App.