Regarding sources on the Aztecs, with the three Nahuatl speaking sub-groups of Mexica (of Tenochtitlan), Acolhua (of Texcoco) and Tepanec (of Tlacopan), there are hieroglyphic chronicles going back to pre-Colombian times, and also later written sources. These later sources were often written by Mestizo scholars related to Aztec nobility, and could be based in part on the older chronicles and even oral sources. One of these scholars that I'm familiar with, Fernando de Alva Cortés Ixtlilxochitl, might be of interest for this question.

Alva Ixtlilxochitl (late-16th - mid-17th C.) was a direct descendant of Acolhua rulers Ixtlilxochitl I and Ixtlilxochitl II, and also related to the penultimate Aztec ruler of Tenochtitlan, Cuitláhuac, so his writings have to be examined before this (Acolhua-friendly) background. In his Historia chichimeca, his main focus other than his direct forefathers lies on Nezahualcoyotl (early- to late 15th C.), a tlatoque or ruler of Texcoco. I don't know if this falls under your category of war captain, Nezahualcoyotl is characterised in the book as a sort of wise philosopher-king, but also as someone who reconquered his capital Texcoco from the Tepanec and later settled a quarrel with his insurgent uncle amongst others - graphic battle scenes and schemes form part of the narrative. According to Alva Ixtlilxochitl, he also made the other Aztec groups pay tributes to the Acolhua, and furthermore his social and lawgiving improvements are underlined. Interestingly enough, the historian also attributes a kind of proto-Catholic background to Nezahualcoyotl (Alva I. himself was educated in the franciscan Imperial Colegio de Santa Cruz Tlatelolco). Beginning with Ixtlilxochitl I, the Acolhua were in the following time subjugated by the Mexica, who became the dominant power in the Aztec Empire before the time of Cortés' arrival.

Another example of a powerful ruler in the Historia would be Xolotl, the first ruler of the earlier Chichimeca (possibly 13th century). This can be seen as more of a semi-'mythical' and less well-documented time, even though Alva Ixtlilxochitl claims to use indigenous sources here as well. He describes Xolotl as leading an army of about a million warriors, for him the largest of ancient Mesoamerica, who subjugated other rulers to a tributary status, and established the Chichimeca-empire (on which laters rulers such as Nezahualcoyotl built) through conquest.

I hope this isn't too long-winded and goes in the right direction. The Historia has to be taken with a grain of salt, as mentioned because of the author's background, and also because of its temporal distance to the described events, but it's still a very readable narrative description of pre-Colombian Mexico, also for the post-classical Toltecs. Other authors from the 16th and 17th centuries apparently often similiarly worked in their respective (Mexica, Acolhua or Tepanec) backgrounds in their writings, sometimes in order to further their own goals or gain higher status in colonial New Spain, as was the case with Alva Ixtlilxochitl.

• Source: Alva Ixtlilxochitl, Fernando de, Historia de la Nación Chichimeca, ed. by Vázquez Chamorro, Germán, Madrid 2000.

• A good general overview of Mesoamerican (including Aztec) history: Mesoamerican Chronology, in: The Oxford Encyclopedia of Mesoamerican Cultures, Vol. 2, Carrasco, Davíd (Ed.), Oxford 2001.

As it turns out, if we expand your period range by about 50 years we come across among the most famous Mixtec rulers, 8 Deer "Jaguar Claw", who ruled from Tilantongo until his death by sacrifice in 1115 C.E. Moreover, we have several pre-Hispanic pictorial codices recording his exploits; the Bodley, Columbino-Becker, and Zouche-Nuttall. The Columbino-Becker and Zouche-Nuttall are the most focused on 8 Deer, with Zouche-Nuttall being an account partly of his family lineage and partly a record of his conquests and exploits and Columbino-Becker more focused on his political activities to the exclusion of his lineage. 8 Deer was not really especially close in line to the throne of his hometown of Tilantongo, but he did manage to attain military success with the aid of his brother 12 Movement and was given rulership at Tutupec on the coast before claiming power at Tilantongo and conquering a large part of the Mixteca Alta through military expeditions and strategic marriages. If you want to read about 8 Deer's activities I would recommend Elizabeth Hill Boone's Stories in Red and Black and Byland and Pohl's In The Realm of 8 Deer, both of which discuss the pre-Hispanic sources on the Mixteca.