Leaving him for short periods of time is a great idea. Socializing them with other animal and people would also be helpful. Plus I think that if you spoil your dog and carry them around too much they tend to be more clingy and over protective. Which like you said can cause agreation issues later on.
Im with my pups 24/7 also but I have never spoiled them to the extent that their needs come before the humans in the house. Dogs need to learn their place in line behind the humans. Not being treated as equals, no matter how hard it is for some to do. We love them and want to give them the best. But sometimes our best is what can cause the behavior issues. Im so glad that my pups are well balanced and dont have too many issues. Their not perfect but they are pretty close ! LOL
Which reminds me of this, this women is nuts
My Cat from Hell: Casting Tapes: Melissa and Mariah : Video : Animal Planet