Vast Increase in build time after Upgrading from VS2015 to VS2017 - visual-studio-2017

Question

Short Version:
Build times for a .NET solution have gone from an average of 12 minutes to 34 minutes.
Long Version:
I had a Visual Studio 2015 solution with three projects in it:
MVC web application targeting .NET 4.5
c# class library for models targeting .NET 4.5
c# class library for data access targeting .NET 4.5
The solution is being built successfully in TeamCity 2017.1.5 using an "MSBuild" build step and the MSBuild 14.0 tools. The TeamCity step has the following flags:
/p:DeployOnBuild=true /p:PublishProfile="%system.teamcity.build.workingDir%\WEBAPPLICATION\Properties\PublishProfiles\PUBLISHPROFILENAME.pubxml" /p:Configuration=CONFIGURATIONNAME /p:VisualStudioVersion=14.0 /p:AutoParameterizationWebConfigConnectionStrings=false /p:SkipExtraFilesOnServer=false /p:DeleteExistingFiles=true
This setup has enabled our continuous integration/continuous deployment for our development server. It may be important to note that locally, we do not build the MVC views, but the build configuration on TeamCity enables MVCBuildViews first thing. This results in speedier development for our team locally.
A need arose for the majority of our models project to be utilized by another .NET project. Because Microsoft deprecated Portable Class Libraries and our models project makes extensive use of the [Serializable] attribute, which is not supported by PCL without numerous changes, we made the decision to change the models project to a .NET Standard 2.0 library project. The end goal is that we will use our private NuGet server to package up this one .NET Standard 2.0 library project as a NuGet package for use in this other project.
We upgraded our development machines from Visual Studio 2015 to Visual Studio 2017, created a new .NET Standard 2.0 project within the same solution, copied all of our models from the older models project to the new project, updated all of our references in the web application and data access project, and changed the web application and data access projects to target .NET 4.6.2. The solution builds successfully locally and is working just fine.
I was able to get TeamCity to build this new version of our solution by making sure the server where the agents are installed has Visual Studio 2017 installed along with the 4.6.2 targeting pack (this part was annoying to figure out). After extensive trial and error, I was only able to get TeamCity to successfully build the solution using a batch file and calling the batch file with a command line build step.
Here is the call from TeamCity:
c:\MYBATCHFILE.bat "%system.teamcity.build.checkoutDir%" "CONFIGURATIONNAME" "PUBLISHPROFILENAME"
Here is the batch file:
"C:\Program Files\dotnet\dotnet.exe" restore %~1\NEWMODELSPROJECT
%~1\..\..\tools\nuget.commandline.4.4.0\tools\nuget.exe restore %~1
"C:\Program Files\dotnet\dotnet.exe" build %~1 /p:Configuration="Release"
"c:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\MSBuild\15.0\Bin\msbuild.exe" %~1\DATAACCESSPROJECT\DATAACCESSPROJECT.csproj /p:Configuration=%~2 /p:Platform="AnyCpu" /p:VisualStudioVersion=15.0
"c:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\MSBuild\15.0\Bin\msbuild.exe" %~1\WEBAPPLICATION\WEBAPPLICATION.csproj /p:Configuration=%~2 /p:Platform="AnyCpu" /p:VisualStudioVersion=15.0 /p:DeployOnBuild=true /p:PublishProfile=%~1\WEBAPPLICATION\Properties\PublishProfiles\%~3.pubxml /p:AutoParameterizationWebConfigConnectionStrings=false /p:SkipExtraFilesOnServer=false /p:DeleteExistingFiles=true
Essentially, we use dotnet restore on the .NET Standard 2.0 project, NuGet restore on the rest of the solution, dotnet build the .NET Standard 2.0 project, and then MSBuild the other two projects in the solution with the MSBuild 15.0 tools and the same flags as we were using before.
We aren't seeing any issue with the solution locally, but within TeamCity, our average build time has skyrocketed from 12 minutes to 34 minutes. It is important to note that no other major change has occurred with the project during this upgrade. The biggest time sink, by far, is MvcBuildViews. Here is a highly redacted version of the build log, as taken from TeamCity:
[10:50:07] The build is removed from the queue to be prepared for the start
...
//all other steps of the build complete in this amount of time
...
[10:50:21] Step 8/15: Run Batch (Command Line) (33m:28s)
...
//the other portions of the above batch file run in this time period
...
[10:51:15] MvcBuildViews:
...
[11:23:50]
[11:23:50] 104 Warning(s)
[11:23:50] 0 Error(s)
[11:23:50]
[11:23:50] Time Elapsed 00:33:16.53
[11:23:50] Process exited with code 0
...
//minor clean up steps
...
[11:23:53] Build finished
These average times are the same whether the batch file is run by TeamCity or manually from the command line. So, to put it bluntly, what has happened between MSBuild 14.0 and MSBuild 15.0 that the MVCBuildViews task takes 3 times longer? Are there flags or options I can pass to MVCBuildViews to improve this build time?