Mistwell
Crusty Old Meatwad
There is an easy fix to Goodberry, although it's not exactly RAW. One goodberry is the equivalent of a day of food. Can you actually eat 10 days worth of food at one sitting? I don't think it's unreasonable to limit the number of Goodberries you can eat per Long Rest. I'd also rule that you can only eat one per round - which means that Cure Light stays useful for combat and Goodberry is for out of combat healing.
You're fixing a relatively obscure interaction of an ability from one class interacting with a spell from another class all due to optional multiclassing rules, at the expense of the normal use of the spell. It's throwing out the baby with the bathwater. The spell is obviously intended to provide the ability to eat more than one berry in a day (it only heals a single hit point per berry, and makes 10 berries, and nobody travels with 10 people in this game). If it bothers you, just disallow this ruling - it's easily done. It's perfectly reasonable to say that the Life Cleric ability says it alters a casting of a spell - and you only cast the spell one time, so just say it impacts just the first berry eaten after the spell is cast.