Objectively, it is nearly impossible to justify the cost benefit, but there are ways to close the gap. At some hotels (AKL), club level also comes with preferred rooms or specific locations in the hotel. If you want Arusha Savannah View anyway, the CL gap is smaller than if you compare to a no-view room rate. The food and beverage options can be pretty good...I have loved some of the choices at AKL, WL, and Poly. That said, if you are a park warrior--rope drop to fireworks, you will rarely be there when the food is available. It would be nice if there were offerings early enough to make park opening, but that is usually not the case (this was pre-COVID and includes morning EMH openings). You would be fine on your EPCOT day under the current schedules.
Concierge cast members are extremely nice, but Disney has provided them no particular tools to be helpful in a meaningful way. Both times I engaged them would have been easier and faster to take care of the issue myself. They basically do the same thing you can do on the apps or online, but do it for you.
Some lounges are in great locations...the Poly has great fireworks and Electric Light Parade viewing. I believe Contemporary is similar, although I have not stayed there.
The morning offerings get pretty bland over a longer visit, and if you are a breakfast person, you will probably break down and get a real breakfast at some point. The daytime offerings are sparse, but that is the best time to relax in the lounge. Most of them are really nice/well appointed areas, but they get very crowded at peak times. In some cases, evenings have remarkably good offerings, although in small portions. You can definitely make a meal of it, but it will take some work on your part. They definitely cater to the kids in the evenings with offerings...chicken nuggets uncrustables, etc. A nice option is to feed your kids there and save a few bucks on your sit-down meal elsewhere.
Booze is a highlight. If you are a drinker the wines are OK, beer is plentiful, and there are cordials available in the evenings. I never saw scotch or anything along those lines, but I know someone else indicated it was available at their hotel. If you don't see something you want, it can't hurt to ask...the cast members working the food and drink part of the CL are extremely accommodating. I asked for and received mimosas one morning. I also made a few trips from the pool to get a beer in a to-go cup. I am not too frugal, but occasionally I did get an attack of, "it is free upstairs and $10 here at the pool.)
For the record, the time when we got the most benefit from CL was when we had infant/toddler age kids. We were in the hotel more due to naps and other kid considerations. In a couple of cases we were close enough to enjoy the club and still be within the baby monitor range while the kids was napping (we brought our own monitor).
If you have the money for nothing but the best or have a resort-heavy stay, CL is nice. If you were to put the extra $$$ into a cost-benefit spreadsheet, you would probably find you could afford some really nice table service meals for the extra money you are spending.
