Yes, to some extent you want to maximize Divisional (or other unit) elements/equipment where and when you can, but as the game is on a operational level (not tactical), these considerations have more operational implications. If the enemy is making a large armoured thrust, then you send more of your anti-armour units and Support Units to that area of the front. If you need to blast through heavy fortifications, then you shift more artillery and engineer resources to that area.
In terms of individual combats, divisions will have very similar levels of elements. One Infantry Division is more or less the same from another (in terms of AT Gun numbers, for example), as long as they have a similar % TOE. It is also situational dependent. In your example, are we talking a Russian Tank Division in 1941 or an SS Panzer Division in 1943? Etc. A Russian Tank Division in 1941 is pretty fragile, and a German Infantry Division on deliberate attack should be able to deal a significant blow to it. An SS Panzer Division in 1943 is going to need a large number of Tank and Mech Corps to do much damage, so in that case I'd rather outmanoeuvre or isolate the SS Division, and damage/destroy it that way.
Ultimately though, yes, individual elements and equipment do play a part in combat, as all elements are calculated and fire in such a manner, so an Infantry Division with 36 AT guns will have a better chance at destroying a larger number of tanks than a Division with only 18 AT guns. But tanks get destroyed in other manners, by infantry, artillery, engineers, aircraft, etc. so it's not only the AT guns that will have an effect on tanks.
Personally, I worry less about the tactical abilities of my units (how many AT guns does the Division have) vs terrain, supply, movement, CV, morale, forts, etc. Some consideration is made to position tank/AT units in areas vs enemy tank units, as well as infantry/artillery/engineers need to deal with entrenched positions.