If your Mother's Eureka is indeed 30+ years old, she would have had a canister that would have cleaned very well. Your mother would be better off purchasing a new vacuum cleaner. With the right choice, the new vacuum would clean the same. What would be better with the new is filtration and possibly noise level. Filtration, including bags, have improved, since that Eureka was made. Multilayer filter bags filter much better than the single layer used for your mother's Eureka. Depending upon which model and brand you look at, canisters with power nozzles can be lighter than that Eureka.

My kids are 7 and 11 and we've had our pool for a few years. The less shallow end the better, IMO. Ours starts at over 3.5' and goes quickly to around 6'. 3.5' is REALLY shallow for adults. Once the kids can swim (and they will learn extremely fast if you have your own pool) they will spend most of their time in the deep end. Adults hang on the steps, float on rafts/noodles, or swim in the deep end, usually. A good/big-enough-to-rest swimout in the deep end is much more essential for safety and is much more used than a flat shallow end, I think.

I would fit a small refrigerator next to the cooler, so that the next owner can remove the cooler, slap up some drywall and paint, and have a correctly sized, appropriately located, already electrified and plumbed space for a nice big refrigerator. You will be fine, since you know how to use the cooler, including what foods can and can't be stored at 45-55F, and your shopping habits can accomodate having only a limited amount of 32-40F refrigerated storage. The next owner will be fine, since with a minimum of effort he can have the large fridge that he'll want instead of the cooler that he won't want. The kitchen layout will be much better, with the sightline and table you want.

I have never heard of a 1/4 in. x 1/2in. x24 in. SS rod. Rods are round. That being said installing plate connectors, steel angles, wrapping in steel C-sections or even a carbon fiber wrap over the interface of the concrete/wood would add stiffness at the "joint". None of these suggestions are especially asthetically pleasing but all would be better than what's there. There is no other information provided about the deck configuation so we don't know the loads in the column. FWIW, bearing on the slab/concrete does not appear to be an issue as I would've expected the concrete to show some cracking or signs of distress already. Short answer to the OP. Constructing a concrete pillar like that and resting a post supporting a column is certainly not the correct way to build a deck support. It looks dangerous and should be addressed as soon as practicable. Call a reputable contractor in your area and get estimates on repair/replacing those supports.