For big heavy vehicles, look for the Germans. The Woden and its associated vehicles all use the same chassis adding a heavy tank, tank destroyer and twin-turret vehicle. Size skirts have been designed to fit this chassis as well.
Three sets of half figures, each in a different style that should fit just about any vehicle crew needs. Sculpted by the very talented Martin Baker, all three sets have identical torsos with different headgear. This not only allows you to use them for different factions, but you can also mix and match in a single faction for that battle worn look.
All vehicle modelers want this stuff and Brigade has done a great job of answering this call and not just with the usual bags, stowage and camo netting. They have also released various turret top systems - sensors, aerials, etc. These are great for adding detail to your rigs or for those cool scratch builds and kit bashes. Brigade has even gone as far as making hatches (where was this in my last round of scratch builds).
More EuroFed Vehicles
The Juin AA and Tassigany (AA and Command) were released in May but somehow escaped our radar (must be stealth). These lighter vehicles will add some useful firepower and variety to your vehicle forces. They also look like the sorts of rigs that might show up in smaller national armies, client states or mercenary forces.
Everyone loves future Russians. Almost every line of near future has them. It makes sense. Brigades offerings in this category are very nice and represent a look that while still saying "Hey I'm Russian" are not simply future T-X tanks. Combined with some smaller vehicles these all share a certain utilitarian simplicity we expect in Soviet vehicles, neo or otherwise. They even released a bunker option. The smaller turrets and sensor pods on these vehicles are also available separately for your converting pleasure.
The PacFed vehicles from Brigade are a very distinct grav design and these latest utility vehicles keep that flow going. While intended as utility vehicles, there is an MG and missile turret design in the mix. With the inclusion of the pintle mounted weapons I can see a combat car coming out of these. I have included one of the earlier PacFed tanks for reference.