Social networks like lemmy or reddit have now replaced the forums in my experience, for the better or the worse.
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I have always felt that lemmy has potential to be that kind of place.
Having said that, I'm new to the game so I look on everywhere I can, including old forums. Like with every experience you want to replicate you could start for defining what you liked about it. Then ask yourself, what in commander could make me feel the same way (not necessarily the same cards, but analogs that capture that feeling). Finally before making a deck, define with which group of players you want to play these decks with and perhaps ask them to be on the same vibe/level as you.
I guess not the response you asked for, but a different approach to get to a similar place. Good luck with your decks!
I've made good experiences on here at least when it comes to rules questions, but obviously it's a rather small community.