No sweat, Andronicus. Great to see you back.

For house rules directed against the Poeni, perhaps you could limit yourself to 20 units in the field at any one time as long as you do not expand beyond Italia. That may help, and perhaps you could also mandate that only 10 could be in the south, in Sicily, while the remaining 10 campaign in the north. Furthermore, if the First Punic is what you had in mind, you could even besiege cities, not build any rams, and conquer Sicily that way. Though that might not actually prove too much challenge unless you manually create units for Carthage in Sicily to oppose yourself. The SSbQ AI does not come across as being remarkably amphibious, even on BI.exe, so it's pretty much cut off as is.

House rules aren't actually meant to make campaigns more realistic, not in all cases anyway. They seem to me to rather be meant to make things more challenging by setting restrictions to slow yourself down. Sorta like savouring good food through small nibbles. As I see it, the only way you're ever going to have any challenge with Carthage is to challenge them in Spain and Africa. No other place will do.

I actually made my Romani campaign more challenging by only winning new settlements by siege for the first 20-30 years. Thus my development was slow while I built my infrastructure, while by the virtue of the money scripts, the neighbouring AI factions would grow faster. The real challenge to the Romani only begins, as I see it, at around 200BC. But even then, no matter how you look at it, the enemy is still more tenacious than challenging.

The dates house rule will put enough on your hands as it is.