Well, being a Continental World I would assume our Habitability is at 80% (although we've employed a lot of Terraforming so perhaps we're higher than that now) - but if we could locate a Gaia World in any Hyperlane-adjacent system, that would certainly be a great 100% Habitability target for any future colony ships.
No need to leave though, we have unlocked gene tailoring and we should we able to research glandular acclimatation now, right?
Considering how unlikely even the most ideal world would be to cater to the exact conditions we've evolved to adapt to, I'd say "more habitable than earth" is impossible without extreme terraforming of a lottery ticket planet.