Frozen spinach is the one for me, hands down. I used to buy those big tubs of fresh spinach and watch half of it turn to slime before I ever touched it, which is basically throwing money straight in the trash. Now I grab the frozen bricks for like a dollar and toss a handful into eggs, soups, pasta, whatever, and it lasts for months without going bad. The key is you can't treat it like fresh greens in a salad, but for cooking it works the same and honestly tastes fine once it's mixed into stuff. Once you start watching what actually gets eaten versus what gets pitched, the freezer aisle stops looking like a scam.

Beans are just plain sun hogs, that is the whole problem. I fought this for two seasons on my east facing porch and every bush type I tried gave me nothing but leaves. What finally worked was Rattlesnake pole beans, they still want light but they climb up and chase it, so the top of the vine gets sun even when the base is shaded. The trade off is they take forever, like 80 days, so you are picking in September while your tomatoes are already done. If your balcony really only gets 3 hours, I would stop fighting it and run two cherry tomatoes in that box instead, maybe a Sungold next to the Sweet 100 for some variety.