PH, we were comparing tanks. And my position is that the quantity of a tank has not much to say about the quality. The crappy PT 76 amphibious tank was produced in large numbers but is total crap. So it isn't on the list. The Mk IV was a tank but had tremendous problems in the beginning. It was a shock for the Germans but soon they learnt how to deal with that thread. In the first battle of Cambrai, where the tank was used first, the terrian won was lost very fast and the few tanks to come into attacking position were soon knocked out.
Yes, the A7V was costly and had its problems. Also the Germans relied more on Stoßtruppen than on tanks. So that most German tank units were fighting with captured Entente tanks.
However if we have to compare the tanks we can only do it directly. Although you are right concerning the loss ratio of 3:1, the German tank was lost by accident. And the only success the British had was damaging the tank of Lt. Blitz who just had destroyed the first tank in a tank to tank combat and damaged another.
So we have to see the capabilities of the tanks. The A7V had a much thicker armour and a speed and range advantage compared to the Mk IV. Only the production numbers let the Mk IV lead by far.
So in the end as, compared 1:1, the A7V was, although having big problems, was the better tank. I only think the Mk IV should not be on the list. And the A7V, too, as it had so much problems. The Renault FT 17 should be OTOH, although being only a light tank.
Adler