Do you already have an Azure investment? If you're using .NET, you already have some MS history, so maybe that's the reason? Not a concern, I'm just wondering.

Just moving the app to cloud wholesale isn't too bad, but rearchitecting/rewriting with a microservices architecture might more effectively provide you with the better scaling you're looking for. You could then use kubernetes pods, and then horizontally scale just in the bottleneck areas. That tends to save more money long term.