[keycloak-user] Encoding theme selection in realm?

We've built some themes, login and email, and configured our Keycloak 1.6.1 such that the theme is available in both dropdowns on the first start of the server, but I'd like to optimize a bit more. Since we import our realms, is it possible to configure them such that our theme is selected without any manual input? On a related note, is it possible to configure the admin user such that we don't need to reset their password on first start of the server? We expect to upgrade to 1.7.x or higher soon, which may be relevant given how the admin account is removed. I'd be curious to know whether my ask is possible on either 1.6.1 or higher. Thanks!