I see gifting SLDs on TLDs as an opportunity to create a trial phase that gets people adopting handshake through Namebase.

Example: Bob owns a TLD, from Nambase.io Bob goes to Products-> Gift SLD. From there Bob gifts Sally a SLD on his TLD.

Sally receives an email from Namebase telling her that she's received a free SLD from Bob and all she has to do to claim it is to click a link in the email. The email link takes Sally to a gifted SLD version of the sign up process. On finishing sign up to Namebase, Sally can go to Dashboard and from her Dashboard she can see a SLD section for SLD's that she's been gifted. From this section she can manage the SLD she's received from BOB and change the domain records for it as she pleases. This gives Sally a sense of real ownership and allows Bob to not have to sit there like a dud and change domain records for his friends and family. A win win for both the TLD owner and the SLD gift receipient.

After a while of owning this SLD, Sally decides she's finished with the trial phase of the customer journey and ready to buy some HNS and start bidding on TLDs.

Attached is a mock screenshot of where i think the sub domains section would sit.

+1 to this suggestion

I would totally use this. Been gifting a few names on and off Namebase. Picking a name relevant to them takes too much time with the 15-day auction and they would've lost interest by then. Also the cost depends on the name and it's availability.

As Namebase is custodial, transferring rights of slds should be possible off-chain. Then with a generic enough tld, gifting a specific sld will be faster and easier. It'll be easy for everyone to test out and dip their feet into Handshake.

There would be some things to take care of like if the name owner wants to withdraw from Namebase, it shouldn't be possible until all sld "owners" have consented.

Now that I see, it's somewhat related to https://feedback.namebase.io/namebase-website/p/dashboard-for-selling-second-level-domains

This could also be especially useful if you had a platform set up on your TLD and accounts on that platform could live on the SLDs. For example, if Twitter had their platform on twitter/, this could make it easy to set up a Twitter account that lives on johnnywu.twitter/