Ace splits
In a 6 decks shoe game, splitting Ace twice (3 hands) gives you an additionnal edge over basic strategy of 0.059%. Being allowed to split 3 times (4 hands) boosts that edge to 0.069%. Due to its rare frequency, being able to split Aces an unlimited number of time shouldn't give you more than 0.07% over basic strategy. A gain of $0.07 for every $100 bet.
This said, the fact that you are counting cards, you will place more money in high counts where more Aces are available and the effect of the rule will probably be a little better but don't expect much. To get a clear view, you'll have to simulate with a particular penetration and bet spread you.