I want to build a Flickr replacement, what do we actually need?

I've gotten back into photography the past couple years and I'm just so disappointed that Instagram is the only place to really share my stuff. There's basically no way to browse for things and no real community, it's all just a big algorithmic slop bucket. I shoot mostly portrait too so having to squash everything to 1:1 messes up my compositions.

I've also worked in tech for a decade and helped with a bunch of startups, so I know what we're talking about isn't even hard to do. You could practically rebuild it beat-for-beat with a coherent sane modern interface and some Google photos style freemium arrangement and it'd pay for itself just fine.

There's no point doing this though if it's just a me too. What do you wish was in there?