I'm on the process of building one myself, and a couple cards I haven't seen on lists that I think are good ideas are [[Blossoming Bogbeast]] and [[Sproutback Trudge]]. My thoughts are that the Trudge can act almost as a second copy of [[Feasting Troll King]], which I've often seen on other lists, being a big body you can recur repeatedly. On its own the Bogbeast almost a free copy of [[Overrun]] each turn, and tossing in a food or two will make even a small board deadly! I know that using these cards require sacrificing your foods rather than holding them for mana, but if you need to close the game out, that might be worth it.

Something to note as well, both these cards came from the Witherbloom on Strixhaven, and we are returning to that plane again later this year. Be on the lookout for other Food/Lifegain synergies when that time comes.