Best Small Companies Making 1/35 Armor Kits?

Fine Molds. Try one of their WW2 Japanese tanks, you will be greatly impressed.

Some others that I have heard nothing but positives about are Tristar's PzKpfw I and Tasca's PzKpfw II Luchs.

IMO, Zvezda, Maquette, Eastern Express and some Skif kits are worth building. They have kits that bigger companies don't or won't produce. They aren't perfect and do need some work, but isn't that the fun of modeling? At least for me it is. Of the companies I mentioned above, I think Eastern Express is the best of the bunch. My advice is to look for them on Ebay (lower prices) and give them a try.