I'd say 2015 and 2007. Yes, while the Phantoka/Mistika were diverse in stature and presentation, you really had to grasp at straws to find any character similarities with the latter (especially Gali).
As drastic as the underwater motif was, the Toa Mahri still retained numerous, even subtle, similarities with prior versions. Take a look at Hewkii: the minimal armor on his body would imply this character is very athletic; very swift. Even his Garai retains the bulging cheeks seen on his original Kakama. Were he to have been taller like his Inika counterpart, I feel LEGO would have captured his character perfectly.
Another example would be Kongu. While his hefty frame is a little too exaggerated, it isn't exactly out of place. Paired with the Dark Green, Silver, and Grey, not to mention the dual projectile weapons, Kongu really seems like a battle hardened warrior. Compared with his Inika form, similar in color and toting two projectile based weapons (one being his crossbow), Kongu is relatively consistent with his prior form. The Zatth's features even harkens back to his old Miru, what with the sleek, calm looking eyes, and the slightest hints of a smirk being shaped by those two slits below.
2015 really kicks it up a notch with the armor placement and body proportions. Now you have sets like Tahu and Kopaka, who both compare in certain aspects, but contrast in others. Kopaka's heavily armored shoulders and boots compliment his more withheld demeanor, while Tahu's bellbottom legs, for lack of a better word, and downward placing armor emphasize his looser, more outgoing character.