You're very wrong if you expect troops to get experienced above 80 maybe 85 without Elite; and that is most rare - for Germany.
Each hit you take will bring in replacements at best at 70 experience so the more troops fight, the more they wear down too. While it is normal to get to 71-75 range, above begins to get a struggle. Especially as you can also get hits when you attack at 10:1.
I find the Elite business very precious but I do not disdain the Anti-Tank one either.
The others are just situational. Sure, an Engineer or a Heavy Artillery are nice to have around, but they're pratically 'attack only' specs. The Winter one is pratically garbage.
The Infiltrator is so subtle that I cannot really feel it - and without awareness of the combat table and its potential results it's just 'uh what? 5% more retreat? But what's my base % of retreat? It can be 2%, it can be 50% ..."
So the way of thinking is to simply pump what you can humanely see - combat factors. That is why Elite is so appreciated around.
Also Elite ramps up with your tech (that 10% Experience will be felt more on a '45 unit than a '39 one in proportion), whereas your 2 Anti-Tank factors are flat bonus through time (And usually I'd say, they may do well enough for Italians, French, and the like).