Кнопка, как TextBlock

<Button Content="I'm a Button; click me">
    <Button.Template>
        <ControlTemplate TargetType="Button">
            <TextBlock Text="{TemplateBinding Content}" />
        </ControlTemplate>
    </Button.Template>
</Button>

https://stackoverflow.com/questions/7769979/wpf-button-no-border-no-background

И стрелочки до кучи

<Button FontFamily="Marlett" FontSize="20" Content="5"/>
<Button FontFamily="Marlett" FontSize="20" Content="6"/>

https://stackoverflow.com/questions/432384/wpf-create-buttons-with-up-and-down-arrows-using-standard-buttons

Листбокс и контент во всю ширину

Listbox Datatemplate that fills full width
https://social.msdn.microsoft.com/Forums/windowsapps/en-US/974fe937-c257-48b9-9a78-3196d964110d/listbox-datatemplate-that-fills-full-width?forum=wpdevelop

<ListBox x:Name="ListBox">  
    <ListBox.ItemContainerStyle> 
        <Style TargetType="ListBoxItem"> 
            <Setter Property="HorizontalContentAlignment" Value="Stretch"/> 
        </Style> 
    </ListBox.ItemContainerStyle> 
 
... 
 
</ListBox>