Absolutely. Heck, the guys which put together NAM are still adding stuff today - 11 years after SC4's release. It would be very ambitious of you guys - a team of 9 I recall reading - to do nearly as much. That's where modding will hopefully come inOoo, sounds like a great mod! I know this might be strange to hear from the people working with the game, but let's be realistic, we won't be able to add all the stuff you want even if we set back the release several years. There's just way too many features and variations of such that could fit in the game. So I really look forward to seeing our modders start patching up and filling out the holes, especially with great mod packages like NAM seems to be.
I hope that C:SL's modding isn't nearly as patchy as SC4's though. NAM has some bugs which crash the game because of inherent problems with SC4, and I believe that Maxis never patched the bug which made it possible for custom residential ploppable functional buildings (modders can do ploppable commercial but not residential). I hope you guys don't abandon the game so quickly like EA/Maxis did with SC4. There are still a lot of bugs left to fix up.