I think it’s a very good idea, and I can’t see any obvious disadvantages except, perhaps, the loss of posting and comment history from the currently existing communities.

Maybe also consider merging [email protected] ? That one seems to be quite general too, and posts often become discussions of how to cook the showcased dish (plus I really dislike the name of the community).

Yes, it is a famously polarizing taste, but a small amount in something hefty like a ragout adds umami without adding too much of the marmite flavour. I’m vegetarian, and find it’s really handy for adding meatiness to such things.

If you try it and like it, do try marmite spaghetti.

Miso, Marmite, MSG, and Maggi are all good.

Not all at once, though.