For me, as for huge fan of japanese JG1 transformers, TF: Zone is the point, where I, to my surprice, is glad that it's production was stopped right after the first episode. If it was continued, Zone could be sufficient drawdown of JG1 line. It still has some good vibes of japanese approach to transformers, but there is too much bitter tar in the pot of sweet honey. As synthetic Bishop said: "If I'll never be top of the line again, I'd rather be nothing".
Let me elaborate my thought. I watched G1 and JG1 TF from 1994 to 1996 (when they were broadcasted in Russia) and discovered Zone only in 2006 via Internet. It was kind of double-edged sword to me. Of course, I was fascinated to see undiscovered japanese episode first time in 10 years, but alas, it's quality was far from Victory, Masterforce or Headmasters. There were no new musical tracks except main theme (even though it was good song). There were almost no new robot characters except two main heroes (powered masters Dai Atlas and Sonic Bomber, for comparison, TF:Victory introduced at least 11 new robot characters in very first episode). There were too many of re-used old characters in Zone as well. Earlier, japanese justified replacing old G1 characters with new unique characters by, say, plot events like destruction of "space bridge", so, after that bridge was rebuilt, it was logical to expect kind of "re-uniting" of old american and new japanese characters into one big and complex universe, but Zone did it lazy. American and japanese characters just reappeared as "nine generals" with silly-looking cloaks being put on them. New leader of decepticons was something unidentifiable, and first of it's orders was to destroy a planet for purpose of... gaining energy to create some planet? I see no sense in it. Plot explanation was never strong in both G1 and JG1, but in Zone it sometimes looks just like random events.
Of course, it still had magnificient vibe of japanese JG1 transformers. Still it was entertaining, dynamic, full of energy and rhythm, still sound and visual effects were good. The scene of planet Feminia and it's destruction was top-notch of TV cartoon quality of that time. Still characters were detailed enough, still fights were badass like in previous JG1 installments. So watching it was pleasant to me even though it was scenario mess. I liked new human and near-human characters like Akira and Kain, they were good enough to tolerate their irritating pokemon-like sidekick. But overall, this show looked like simplification and decline of marvelous japanese JG1 transformers, shifting them in direction of super-cheap and overall random-looking anime stuff with a lot of re-used material and generic anime tropes. If previous three TV-series had a good balance between western animation and japanese mecha anime, Zone lost this balance. So, for me it's only 6 of 10. One single episode was enough. I even personally prefer to consider events of Zone and later TV Magazine story pages to be not existing in japanese continuity of TF. Zone is still better than american G1 though...