WPF XAML側のみでユーザーコントロールに異なる値をバインドしたい

こんにちは。

Textに色々な役割を持たせすぎてしまいますのでこれは好ましくありません。
UserControl自体を別で作成するか、レイアウトを切り替えるプロパティを別途用意しましょう。

<Window x:Class="MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:VisualBasic.Wpf.Samples"
        mc:Ignorable="d"
        Title="MainWindow" Height="300" Width="300">
    <StackPanel Orientation="Horizontal">
        <local:UserControl1 Text="Control1_A" LayoutType="Control1" />
        <local:UserControl1 Text="Control1_B" LayoutType="Control1" />
        <local:UserControl1 Text="Control2_A" LayoutType="Control2" />
        <local:UserControl1 Text="Control1_C" LayoutType="Control1" />
    </StackPanel>
</Window>

<UserControl x:Class="UserControl1"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             mc:Ignorable="d" 
             x:Name="uc"
             d:DesignHeight="20" d:DesignWidth="50">
    <Grid>
        <ContentControl VerticalAlignment="Top" Width="100" Margin="10" VerticalContentAlignment="Center">
            <ContentControl.Style>
                <Style TargetType="ContentControl">
                    <Style.Triggers>
                        <!--2つのコントロールを区別する方法 → LayouType依存関係プロパティで切り替える例-->
                        <DataTrigger Binding="{Binding LayoutType, ElementName=uc}" Value="Control1">
                            <Setter Property="Template">
                                <Setter.Value>
                                    <ControlTemplate>
                                        <Border Background="#FF00A0E9" Height="40">
                                            <TextBlock VerticalAlignment="Center" TextAlignment="Center" 
                                                       Text="{Binding Text, ElementName=uc}"/>
                                        </Border>
                                    </ControlTemplate>
                                </Setter.Value>
                            </Setter>
                        </DataTrigger>
                        <DataTrigger Binding="{Binding LayoutType, ElementName=uc}" Value="Control2">
                            <Setter Property="Template">
                                <Setter.Value>
                                    <ControlTemplate>
                                        <Border Background="#FFEE7642" Height="20">
                                            <TextBlock VerticalAlignment="Center" 
                                                       TextAlignment="Center" 
                                                       Text="{Binding Text, ElementName=uc}"/>
                                        </Border>
                                    </ControlTemplate>
                                </Setter.Value>
                            </Setter>
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </ContentControl.Style>
        </ContentControl>
    </Grid>
</UserControl>

Public Class UserControl1
    Public Property Text() As String
        Get
            Return CType(Me.GetValue(TextProperty), String)
        End Get
        Set(ByVal value As String)
            Me.SetValue(TextProperty, value)
        End Set
    End Property
    Public Shared ReadOnly TextProperty As DependencyProperty = DependencyProperty.Register("Text", GetType(String), GetType(UserControl1), New PropertyMetadata(String.Empty))

    Public Property LayoutType() As String
        Get
            Return CType(Me.GetValue(LayoutTypeProperty), String)
        End Get
        Set(ByVal value As String)
            Me.SetValue(LayoutTypeProperty, value)
        End Set
    End Property
    Public Shared ReadOnly LayoutTypeProperty As DependencyProperty = DependencyProperty.Register("LayoutType", GetType(String), GetType(UserControl1), New PropertyMetadata(String.Empty))

End Class