Hello,
1) Checked your site but I don’t understand what exactly you want to implement with header. Could you, please, provide us with the screenshot of the result you want to achieve and also WP Dashboard access to check the settings you use?
2) What white space do you want to remove? Provide a screenshot for better understanding. You can use the Lightshot screenshot tool to share screenshots.
3) Additional customization or content management is not included in our support, so we don’t have a price for this. We are able only to guide you with theme options. If you need personal customization you need to hire a developer. For example WPKraken team.
Regards