Joining the rest of the tildeverse?

I am part of cosmic.voyage but from the post about mailing list, it
seems I should join some other instance as well, to be a part of the
larger verse? What do you recommned?

if you're interested in other tildeverse members, see 
https://tildeverse.org/members/

yourtilde.com and tilde.team are both strong tildeverse members :)

it is? i thought yourtilde.com was dead

It's alive. It was on life support for a while, but it has a new admin now for
daily monitoring and updates. It will hopefully return as a strong
general-use-tilde option.

That being said, there's nothing limiting anyone to just one or two. Feel free
to sign up for all the tildes you want. :)