I'd like to mention that in fact RomeTW-BI.exe adds nothing to AI strategic behavior.
The common rumour that RomeTW-BI.exe-AI is more likely to capture islands than RomeTW.exe-AI is a myth.
I've finished 3 campaigns with RomeTW.exe-AI and I can say that RomeTW.exe-AI also invades islands when he considers it is well worth it. And it is worth it only if you don't have where else to expand on the mainland.