I haven't read everything up to this point, but if you are definitely looking at homeschooling down the road (which will probably be a really great fit for your kids), I would definitely look at a very low academic, high play social skills style preschool. I have a daughter who just turned 4 who academically could do kindergarten or beyond without a problem. She is about to attend her 2nd year of a neighborhood 3 morning a week play based, open ended preschool. Her teachers really "get" her and if kids are reading or writing and want to work on that in class, it's no problem. The teachers accommodate for kids in all places but really push positive social interactions. It's been quite ideal for her.
And just because your kids weren't speaking at 2 weeks doesn't mean they can't be very gifted. I didn't even suspect my son as being more than a "little gifted" until he got to kindergarten. He is likely going to be home schooled for 2nd grade in the fall. You're way ahead of the game and you're following your kids lead. That's great! Keep up the good work!
