I haven't looked enough under the hood - but, besides SSL issues, what are the most significant hurdles to user customization the URL that points to their pages/content. I'm thinking something like the way web servers allow "virtual hosting" of multiple domains on the same IP address. How hard would it be to allow the same hubzilla instance (or a subsection of a single instance) to be referred to by a custom domain (for example, optimally the ability to have everything related to my user could be under zot.mycustomdomain.com/... instead of hub.webgoeslocal/xxx/dm42/xxx or even www.mycustomdomain.com is an alias for hub.webgoeslocal.net/page/dm42/xxx)?
I'm thinking like "Wordpress.com" allows you to bring a custom domain name and use it to connect to your Wordpress site, what problems would be involved in allowing (1) just a straight "alias" for the domain or, even better, (2) allowing for instance a custom domain for your own WIKI or Webpages or even shopping cart?
I'm mostly looking for a beginning list of "these things are going to be the toughest to overcome" or "these are the things someone trying to implement such a change probably wouldn't think of/consider."
I'm NOT at this point thinking of having customizable channel identities (the same channel referred to using different domains - kind of like clones, but without them being on separate servers) unless it's easier than I'm imagining. As a first pass, I think making it work with "public only" content - maybe even only aliasing certain modules would be easiest - though the goal would be to allow people to magic_auth into the aliased instance to access protected content while retaining the custom url.
Like it or not, most people are not sophisticated enough to realize that the lack of a recognizable domain name in the URL bar means absolutely nothing about the "realness" of the entity supposedly running the web site. Most people using the internet still think that it takes significant resources to just have your own name show up in the address bar and use it as a mark of legitimacy of the site. That hold is slackening slightly, but I don't think it will ever go away entirely.
Ultimately, i think especially commercial adoption / use of Hubzilla would be aided significantly by such a mechanism.