Here are the talent builds I use for primary commanders in the open field in Rise of Kingdoms. Note that secondary commander builds are not used at all, so are not important. Note which commanders you should invest in I cover in my meta watch blog, the below list has those and some others, but only invest in that list.
My current primary commanders
Gorgo [Garrison/Defense] – Garrison build
Zenobia [Garrison/Support/Infantry]
Gorgo rocked our kvk6 garrison, especially since she can garry an offensive archer tower. 2nd is Constatine and I use Lucky Coin and Greatest Glory with this build. In kvk7, Zenobia as primary with Gorgo 2nd worked very well.
Guan Yu [Skill/Infantry] – Open field
Alexander Nevsky, Huo Qubing [Skill/Cavalry] – Open field
Zhuge Liang [Skill/Archer] – Open field
Charles Martel [Defense/Infantry] – open field
Martel should not be in your marches if you can help it, lots of better options now.
My current secondary commanders who could do well as prime commanders if needed
Scipio Prime [Infantry/Support] – open field
Boudica Prime [Archer/Skill] – open field
