As a guy who have watched all three seasons of Ikkitousen (also wrote review for each of them), I will be briefly going over a few pros and cons about this third season, named Great Guardians (GG).
Unlike the previous seasons which focused greatly on the story of Romance of the Three Kingdom, GG was different (primarily due to the apparent defeat of Sousou in Dragon Destiny). As some of you may already know, GG is completely original (*I treat it like a "filler" series*). So not much previous knowledge of the first 2 seasons are required in order to understand GG.
Story:
The story is very weak in GG. It is basically one random event follow by another until half way through the show. As mentioned above, since GG did not follow the Romance of the Three Kingdom, the story is bound to "suck". And the fact that the "villain" is a villain because of such trivial matters doesn't help the story either. As mentioned in the discussion board by some viewers, the director basically "reset" everything back to the way it is at the end of DD (with the exception that Toutaku is confirmed alive).
Art:
The overall animation isn't bad though not much improvement when compared to DD...and ecchi guys will like to see the occasional nude Hakufu etc.
Sound:
The sound for this series is actually quite outstanding especially when compared to the previous seasons. Both the OP and ED received good ratings from fans as well.
Character:
It was nice to see for a change that they focused a bit more on character development rather than just introducing tons of characters that just show up for 30 seconds before getting killed. There is basically just two new characters added to GG so that might explain why they have the spare time to develop the characters more than the prior series.
Enjoyment:
It was very enjoyable for the most part for someone who have seen Ikkitousen's all three seasons. The only department that was really lacking was battles. There just weren't any that can be compared with Dragon Destiny's.
Lastly I would like to comment on the name. I know this will be quite debatable, but in my opinion I don't see how the name relates to this series at all. But since I am not a picky person with names, I'll let it be and it didn't affect my grading of the show ><