Utilizing journey builder interactions for sending post-purchase communications to customers, what contact entry mode fits?

A small restaurant franchise wants to implement Marketing Cloud to support their franchise owners. The owners of franchised stores add a customized local message to the marketing campaign.
What hierarchy should be recommended?

A customer wants to display a subscriber's first name and the date of send in its monthly newsletter. Subscriber first name data is stored in a data extension that will not be used in the send definition.
Which option should be in this scenario?

NTO wants not only to send to their best customers, but also those most likely to buy.
What data will be helpful to send out an email which increases purchase frequency? Choose All that apply

A daily deal website is concerned with their sender reputation and needs consistent visibility into subscribers who report their email as spam.
How can they determine which subscribers reported their email as spam so they can flag those records in their customer service database?