I do not want a G3. At least, in the current climate. Here's why:
Lego has given me zero confidence that they would be able to handle a BIONICLE G3 in a way that would be satisfactory. As the years have gone on, and more info has come out regarding G1 and how it was handled, it's become increasingly clear to me that G1's widespread success was likely luck. All the right circumstances and all the right things happened at just the right time. Trying to recreate that perfectly would most likely be like catching lightning in a bottle.
The mistakes, the mismanagement, the ever-present feeling that constraction will always receive less attention and marketing than the system themes... Lego seems to have extreme difficulty, in today's climate, adapting BIONICLE for modern kids. Lego has given me no reassurance that any possible G3 wouldn't suffer from those same issues. They COULD realize that they need to go back to their old way of handling BIONICLE's plot and marketing, OR they could look back to G1 and how its sales declined due to the complex story preventing new fans from jumping in... and keep things the same, or try to alter the formula in some such way once again.
Plus, so long as BIONICLE remains a constraction theme, in today's Lego world, where System themes with TV shows are the main focus and Lego spends all their marketing budget on them, it will never receive the amount of promotion and marketing it needs to grow a large fanbase. If BIONICLE came back as a System theme... I'd be singing a different tune, but that's another matter.
I guess the point I'm trying to make is that Lego isn't stupid, they do take notice of the theme's problems and attempt to fix them. I firmly believe that everything done in G2 was done in response to what they "learned" from Hero Factory, seeing as how it's become increasingly clear that they used it as a test-bed for ideas for BIONICLE's reboot basically from the moment it was launched. Lego saw G1's stagnation as a problem that they needed to fix with future themes, which is good... but there's many different solutions to those problems and I have no way of knowing how Lego would go about "fixing" BIONICLE in G3, G4, or any future reboot of the franchise.
It's that ever-present uncertainty and the lack of faith that G2 has left me with that make me think it would be far better for everybody if BIONICLE either returned as a System theme so it could receive the necessary focus and marketing it needs, or just stays in the hands of the fans forever. Trial by Tahu, Reviving BIONICLE, Okoto Origins... these are just a few examples of the exemplary fan projects out there that are infinitely more satisfying than anything official that we got from G2. If we want BIONICLE to be successful, we don't need to crawl on our hands and knees, begging Lego to bring back G3 and "do it right this time." How about we just do it right ourselves? We have all the capabilities in today's modern world. Technology has advanced at an extremely rapid rate. Elaborate stopmotions are being done by MNL, SuddenlyOranges makes me care more about characters than Lego's BIONICLE, quite frankly, ever has, Failsafe42 is making a CGI fan-film, Pereki manages to perfectly represent that classic BIONICLE feeling with infinitely fewer resources and manpower than Lego had, and fans like Cyber-hand have even taken to making their own pieces on Shapeways! As far as I'm concerned, leaving BIONICLE's fate in the hands of Lego rather than the fandom, at this point, is too much of a gamble to truly put my heart and soul into hoping for it. The fans are increasing my enjoyment of BIONICLE as a franchise, whereas Lego was detracting from it.