Zend certified PHP/Magento developer

Magento 2 – Order Scalar Extension Attributes – Where to store

I need to store few disjoint scalar custom information on a completed sales Order in Magento 2 and display them in a completed Sales order detail view in the Magento admin and also in the Sales order listing page.

From my initial research it appears I need to use Extension attributes but what is not clear to me is how or where to design the “persistence” of these custom Order attributes/information?

1> Should I be writing db_schema updates ? Should I consider adding them as Schema updates on the ‘sales_order_entity’ table directly? Or bunch them up and add it in a separate table linking to the sales order table. And try to use Magento’s extension attributes to retrieve this information? My fields involve varchar,int,boolean to store the custom information.
If there are code pointers/articles are there, that would be most helpful.

2> Also, similar information will need to be stored in the quote tables also eventually because this custom data will be translated from the cart to order. But I figured if I can get a good grip on one entity, I will be able to transpose this information to another entity unless there is a specific translation from quote to order that I need to be aware of because they are so closely linked.

Thanks in advance.