The answer to 'what size panel upgrade do I need' is that the size of the electrical panel upgrade you need depends on the current and future electrical needs of your home. As a general guideline, most homes today require a 200-amp electrical panel to accommodate modern electrical loads and future growth.
The specific panel size you need will depend on factors like the size of your home, the number and types of electrical devices and appliances you have, and any planned renovations or additions. It's best to have an experienced electrician assess your home's electrical needs and recommend the appropriate panel size.