Like you, I bet, I get really tired of using the same default map. It can get booorrrriiiiinnnnngggg. Here’s a really quick way to create a new map style. (FYI: a "style" refers to what a map looks like–the colors and shapes you use, the background, line colors, etc. A "template" can be all of that PLUS actual content such as topics that include the days of the week if it is a planning map, or of typical project elements if the map is designed to manage routine projects).
Right click on the center topic, main topics, subtopics (as far down as you want to customize) and use the Topic Format options to get the look you want.
Right-click in the open space to pick a new background! (Blue and orange spirals for a background??!! Very cool–just remember to make them pretty transparent so you can actually read what’s on the map…or not…:o)
Once you have it all formatted the way you want–and this is the critical step in Hobart’s Fractured Mapping–to delete all topics, leaving just the Center Topic.
Now go to Tools–> Template Organizer and use the drop down "Add New Map Template" and choose "From Current Map."
Once you have a map you like, just go to Format > Style > Make current map the default. It will then be used for all new default maps with no need for all delete/rename New Blank Map stuff. (Thanks to Robin Capper for this suggestion!)
Just repeat this process every couple of months so avoid the dreaded Boring Map Syndrome. Worked for me. Let me know if it works for you.