It could also make him more responsible. Potter Manor is his family's legacy, so he would feel the need to take care of it. This could translate to him being more responsible in other aspects of his life, like his studies at Hogwarts and his relationships with his friends. He would have to manage the manor's magical protections and secrets, which would require maturity. For example, he might have to learn complex spells to safeguard the manor from dark wizards, and this would force him to study harder. In addition, he could use the manor as a place to host his friends during holidays, which would improve his hosting and social skills. He would learn to be more accommodating and make sure everyone is having a good time, just like a proper host should. All these experiences in the manor would gradually shape him into a more well - rounded and responsible person.
The Potter Manor could make Harry more confident. Living in a grand and important family home might give him a stronger sense of identity. He would know that he comes from a long line of great wizards, and this could boost his self - assurance in his magical abilities.