Hello There,
Thank you for the clarifications and for providing the information.
1.) To increase the font size of the header and navigation, please go to X > Launch > Options > Header. Please also do not forget to set the default font sizes in X > Launch > Options > Typography
To change the font size for your footer, please add the following CSS code in the X > Launch > Theme Options > Global CSS (http://prntscr.com/evui3r) because by default it is se to 10 pixels only.
.x-colophon.bottom {
font-size: 14px;
}
Feel free to change it.
2.) Please edit your homepage and find the columns containing the stats. You can remove all the skillbar elements by emptying/ erasing the column. You can then make use of the map element and insert your map.
3.) All your widgets can be manage in Appearance > Widgets. You may assign them in the different widget areas. To know more about widgets in WordPress, please check out this codex;
https://codex.wordpress.org/WordPress_Widgets
4.) When you create pages and want to link to the page in the menu, you will have to add it as a menu item. You can manage your menu by going to Appareance > Menus. To know more about menus and how you can create or edit it, please check this out:
https://codex.wordpress.org/WordPress_Menu_User_Guide
5.) With SEO, you can make use of 3rd party plugins such as All in one SEO or Yoast SEO plugin to do the job for you. For security, as long as your WordPress, theme and plugins are up to date, you should not worry all about it. And for updates, I would recommend that you create a staging site. This is very useful because you can test drive any updates in the staging area, do the customizations and troubleshooting without disrupting your live site. Once everything is perfect, you can easily and flawlessly proceed the update in the live site. To know how to create a staging area, please check out these articles:
Hope this helps.