Ask HN: Username Discriminator Character?

After following the discord drama regarding getting rid of the hash discriminator on usernames, and currently building a niche social network I thought it would be a good to ask the HN community for advice regarding usernames.

The discord drama seem to point to that the discriminator is the way people prefer it, so lets assume that is the way to go, what character would you recommend as the separator? the hash (#) is only client side, and creates its own issues, so here are some other examples:

username prefixed by discriminator:

domain.tld/7318@victoria

domain.tld/7318-victoria

domain.tld/7318_victoria

domain.tld/7318+victoria

domain.tld/7318:victoria

domain.tld/7318!victoria

username suffixed by discriminator:

domain.tld/victoria@7318

domain.tld/victoria-7318

domain.tld/victoria_7318

domain.tld/victoria+7318

domain.tld/victoria:7318

domain.tld/victoria!7318

Any other character suggested? any better solution suggested?

grateful for any input, have an awesome day!