Why was repeating that build in 2007 suddenly such a problem? After all, the Toa Mata build was repeated for the Toa Nuva in 2002 and Takanuva in 2003, and the Toa Metru build was repeated for the Toa Hagah in 2005. Even the Bohrok had exact clones in the form of the Bohrok-Kal. As I understand it, most people didn't get especially tired of the Inika build until its third year in 2008, and that was partially because people had hoped for new Toa Nuva sets to have a build that better echoed their original designs.
I'm going to through my opinion into the mix. I thought Bionicle did pretty good up until 07 when they started repeating the Inika and piraka build. I Like all the years, but seeing the inika build over and over again was a little annoying. But hey, minor complaints I guess. It's really hard to keep coming up with new designs when you get a really versatile one. I have to admit, I find the inika and piraka builds very versatile. Feel free to disagree with me if you happen to disagree, but please be respectful about it.
There's a reason I consider the Toa Inika build one of the most versatile builds in the history of BIONICLE canister sets. Many sets that used the Toa Inika torso used it with different armor (see: Carapar, Toa Mahri Jaller, Toa Mahri Matoro, Gorast, Mistika Toa Onua, Tarix, Vorox, Vastus, Stronius, and Mata Nui), or sometimes with a different build altogether (see: Mantax, Gadunka, Strakk, and Skrall). Only a handful of sets (Toa Mahri Nuparu, Phantoka Toa Kopaka, Phantoka Toa Lewa, Gelu, and Ackar) used the Toa Inika's torso constructions more or less "as-is", the same way the Toa Inika had used it.
Generally, the best parts are the ones that are designed for long-term usefulness, and that is why I love the Toa Inika torso so much. New torsos were introduced for certain sets like Toa Mahri Kongu and the Phantoka Makuta. Other sets, even more admirably, had custom torso designs based almost entirely on existing parts (Ehlek, Takadox, Pridak, Strakk, and Kiina all qualify). And plenty of titan/warrior sets were even able to use the Toa Inika torso very effectively with original armor designs. So it's not like the Toa Inika torso was used as a substitute for creativity. Rather, I feel it was used as a substitute for introducing wasteful new parts that didn't make any real functional improvements on what was already available. Part of why complaints about the Toa Inika torso always bothered me is that people didn't seem bothered because there was any problem in particular they wanted to see improved. They just wanted something new for newness's sake, and wanted an amazingly functional torso to disappear to make way for it.
What bothered me about post-2006 canister set series more than their builds (which generally continued to be wonderfully complex and diverse, with sets that reused existing torso designs making up for it in other areas) was the length of their arms and legs. Horrendously gangly proportions were the order of the day, since there was only a limited range of sizes for arms and legs, and since the torso proportions of sets had stayed roughly the same size since 2004 while legs and arms got up to five modules longer. Thankfully, Hero Factory's Character and Creature Building System has fixed that and ultimately restored sets to proportions that often rival 2001–2005 canister sets in terms of how natural they feel.
As far as story was concerned, I definitely disagree with this topic's premise. 2007 and 2008 were some of my favorite years for story. Obviously 2001 to 2004 have their own appeal, but they weren't without flaws. The second comic of 2001 ended with a cliffhanger that was never resolved. The Bohrok-Kal storyline felt somewhat tacked-on and had the Toa Nuva go their separate ways, despite two story years' worth of adventures having shown them that they were strongest together, and their new mask powers reinforcing that fact. The scenery of Mata Nui was beautiful, but it also became a bit repetitive to see the same settings every year with few changes, and even have the same sort of "mysterious underground structure" for each and every story arc's final showdown. Now, this doesn't mean I didn't love the early years of BIONICLE, but every BIONICLE story year had its flaws and its merits.