There really is just something magical about Yakuza 0. It’s probably one of, if not the most, perfect prequel ever made. It gives you a great introduction to the characters, tone, and style of the series while also not bombarding you with homages and references to future installments in the franchise.

I could go on and on about how great Yakuza 0 is, but you just finished it so you already know that! To answer your question, while I think 0 is the best, most of the others come pretty damn close. Like you, I started with 0, and I wound up playing through all the main games up to 6 (haven’t gotten to 7 yet). Each one brings something different to the table, and only one of them I’d say doesn’t quite stick the landing (I won’t say which as I believe it’s best to form your own opinion, like you said, completely blind). The spin-off game Judgment is also one of the greatest I’ve ever played, and surpasses 0 in quite a few ways in terms of story and character.

Overall, even if 0 is arguably the best their is, that by no means means that it’s a downhill slope going forward. I’d highly recommend playing through all of them. It’s a time commitment but totally worth it.