In terms of "worth it" from a monetary perspective, it depends on whether your party drinks alcohol and how much you can take advantage of the lounge and offerings. I think dinner is easier (mealwise) than breakfast, but as
@GADisneyDad14 said, that depends on your touring style; I'm a habitual rope dropper, and it can be hard to cram in coffee on very early days, especially if you are using Disney transportation. If you intend to spend a lot of time relaxing at the resort, you may well find it worthwhile just to have a private area to get away from the din (some of the din, anyways, because the lounge may also be packed at certain times of day in April). I have started to stay non-CL more recently, but I still find value during party season - August/Sept because if it's miserable outside with heat and rain, I like to hang in the lounge, and Nov/Dec because - well, the holidays. A split stay might be a good way to try it out.
Can't answer allergy Qs

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