Hi @Nuts, welcome to the forum!!
RE: new units, I think there are some fun options and at least one no-brainer: if you’re playing G40, those Somua S35’s go right in as drop-in replacements for the blue T-34s in G40! Finally!!
Pzkpfw IV’s should also go right into the german armor unit mix, of course, especially for the first few german tank builds, along with the ubiquitous Panthers and a Tiger or two from 41. For G40 the CMP Trucks and LRDG Jeeps can do the same for British Mech Inf., since both the Italians and Russians (and French… sigh) already use use a Truck/Truck-ish sculpt for Mech Inf anyways.The problem with the rest of the units is the limited number of powers with the sculpts available.
The Tactical Bombers are great but if you aren’t already into G40 then you’re only getting a handful and for only a few powers. Do the British and Americans get them? I only see German & Italian Tactical Bombers so far. The Sd.Kfz armored cars make for great Light Armor pieces, but there’s only Germany and Italy represented. The 6-Pounder’s can swap in/out for British artillery in most systems. I don’t play with dedicated AT guns - and then, only the British have a sculpt.There’s the multiple copies & paint option, of course… but if you’re buying multiple copies to paint units you’re much better off looking at all of the incredible community support and high-detail sculpts that have been created for A&A at places like HBG, IWNGU, Combat Miniatures, and even my own web store.