What would you suggest as an alternative to WP Engine?

I am looking to move a particular site away from WP Engine after mounting problems with security and reliability. The site is a content-based site for a $100M entity, and it receives about 30,000 visitors per month. Budget is $500 / mo., though that should be an absolutely unnecessary amount to spend.

The WP Engine sites are in a shared environment, which caused one of two recent problems, and all sites actually run SLOWER than the same thing installed on a dedicated virtual instance / droplet in Cloudways, which I refuse to use for something for which I want quality support, has an actual budget, and that needs to have virtually 100% uptime.

Is a dedicated platform even necessary? See, I have worked with Liquid Web’s dedicated products in the past when it comes to Microsoft SQL and Microsoft .NET, and because they have been an OUTSTANDING company to work with, I gave them a call this morning to discuss their WP offering. But it is still in a shared environment…which they dismissed by saying “oh, we include TEN PHP workers, which our competitor, Kinsta, charges $900 for, so you’re getting a good deal.”

I am not sure where to turn. WPMU DEV? Pantheon? Something else? I do want something that has outstanding support that will dig deeper than just resolving any issues that crop up with the platform itself. For this, WP Engine has been amazing, and I don’t want to lose that ..

Thoughts? Suggestions?