Plus, I mean, unless you're using a Threadiverse host as your home instance, how often are you typing its name?

Having a hyphen is RFC-conformant:

RFC 952:

1. A "name" (Net, Host, Gateway, or Domain name) is a text string up
to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus
sign (-), and period (.).  Note that periods are only allowed when
they serve to delimit components of "domain style names". (See
RFC-921, "Domain Name System Implementation Schedule", for
background).  No blank or space characters are permitted as part of a
name. No distinction is made between upper and lower case.  The first
character must be an alpha character.  The last character must not be
a minus sign or period.  A host which serves as a GATEWAY should have
"-GATEWAY" or "-GW" as part of its name.  Hosts which do not serve as
Internet gateways should not use "-GATEWAY" and "-GW" as part of
their names. A host which is a TAC should have "-TAC" as the last
part of its host name, if it is a DoD host.  Single character names
or nicknames are not allowed.

RFC 1123:

   The syntax of a legal Internet host name was specified in RFC-952
   [DNS:4].  One aspect of host name syntax is hereby changed: the
   restriction on the first character is relaxed to allow either a
   letter or a digit.  Host software MUST support this more liberal
   syntax.

   Host software MUST handle host names of up to 63 characters and
   SHOULD handle host names of up to 255 characters.

Ya, I know. But a few months/years, it is going to be even harder.

indieTalk.TLD indieBoard.TLD indieForum.TLD indieIndie.TLD indieGaming.TLD indieLemmy.TLD Indielem.TLD indieVerse.TLD indieUniverse.TLD indieMingle.TLD indieNow.TLD indieSocial.TLD indieFriends.TLD indieBros.TLD indieBig.TLD

Just some ideas. If you decide to keep the domain name, I wish you the best. Regardless, welcome to Lemmy brother! The more the merrier.