Some choices
> Thus, these Ace side count playing strategy deviations could also
> be used on HOII/AOII bringing these systems to outperform TH-Expert.
Yes, that's just one example of how the books could be used by someone who wants to use a different count system. Either way, the difference of 2-3% one way or the other is insignificant compared to the 10% or greater difference between T-H Expert and all other single-level counts.
> What I am interested in is a relatively simple count system that
> can be used for pitch games and 6 deck games. Did you study any of
> these systems that can be used relatively well?
Did you also look at the Bushido systems? There are running count (Bushido Intermediate) and true count (Bushido Advanced) flavors to choose from. Bushido Advanced is nearly as strong as T-H Expert in many games, with no side count required. And you could even switch between the counts just by counting 7s and Aces as 1/2 point.
> Do your serious of books have any information on using "one system" for all games?
Every one of the systems has a detailed set of System Reports covering the same 20 standard games detailed in T-H Basic Blackjack. In addition, the Intermediate volumes also include extensive coverage of various rules variations found all over the world, presented in a series of another 20 reports. These are real games that all exist in multiple locations today, not just various permutations of a few rules.