Thanks for the heads-up! I've been eyeing Flywheel for a long time, and saddened now by some of these limitations. I was surprised and concerned about the lack of some utilities you mentioned: db admin, access to wp-config, and inability to clear the cache. I wrote to them to verify this was accurate, because those are pretty much deal-breakers. Below is their response, and then my comments:

1. We have an online database manager https://getflywheel.com/wordpress-support/can-get-access-database/
We do also offer direct db access for an additional fee.
2. The wp-config file is locked down, but our support engineers can make edits for you as needed.
3. You can clear the cache from the Advanced tab in the dashboard. https://getflywheel.com/wordpress-support/how-do-i-clear-my-cache/

1. It's not as full-featured as phpmyadmin, but it looks similar to what I get at Cloudways, and at least it lets you import, export, and do the most common functions. I could live with that.

2. I don't like not being able to access wp-config myself. :( Boo hiss.

3. I hate it when they answer a question you didn't ask and pretend that solves your issue. So there really is no way to flush the cache within WordPress, which is dumbfounding and unheard of.

Sure, glad to help. What they told you is true, but that doesn't make some of it any less appealing...