Ditto on Agents comments. Try at least one new piece and see how you can tweak your build. If we are suggesting it yuo can bet your opponent is expecting it as well, add some USEFUL unpredictable units that can work well with he build.
Assuming you stick with what is on the cards (and not go with the recost)
Vet Tiger : is a must. The crack shot is worth too much not to. I once went up against 4 armor units taking out all (I lost my Tiger to a crock but took him down as well).
SS PG: Cheap and powerful
Wehr Snipes; Another "don’t leave home without them. The crackshot again is vey useful not to mention the SA, head shot. I fielded two once and stopped two crocks in their tracks. This allowed me to take them both out with my Tigers very early in the game.
SS haupman what cha ya ma jigger. +3 and cheap + SA. the ober is nice but pricey
I like the hetzers if your short on pts. and need some decent tank killers. (there are other thing out now with the recost that may be better. 20 points each.
Jagd panther (RECOSTED) is 39 that is real good for that kind of armor and punch.
Look at the Panthers as well.
SS determination is a great ability bt you pay pay for it. I think the Panther and a PZ IV have that (Not sure).
I have broken even on the Nash. but must agree with Agent 20 hexes with superior ops is somethingyour opponent won’t ignor(just be careful of the planes.)
Simply put look for stuff with crack shot it almost always helps. If you know yo somehow rol a lot of ones add an ammo dump. (this just helps your odds along).
If you go with the recosted stats these optons ae still, in my opinion, goodthe King becomes viable but I usually stick with the vet anyway.
As far as Allied units I just decimated an opponent with three 81 mm mortars (Improved indirect fire is the best). Agains infantry they rule.
Hope this helps