I don't know if the following comments are useful but here goes...
Here is the picture of this attempt
Looks nice.
For those who have familiar the 5.2 MSI installer already, what I have added is a checkbox "Standard configuration", explanation text, and
For those that "aren't" familiar or are new to the installer I'm thinking a "small question mark surrounded by a circle" next to the 'Standard Configuration' textbox that when hovered over popups a more detailed description of what "standard" means for MariaDB. This would be in lieu of the text below the checkbox. This might make sense to have for the other fields too. Just a thought.
1) default_storage_engine=innodb
I think the storage engine that replaced innodb is now technically xtradb but I believe the configuration option "alias" innodb still works for compatibility. Would it make sense to point this out?