Just started using scratch this spring and like it. A little more palatable than liquid IV and pedialyte. They also have a few that include some caffeine if that appeals to you.
Another option is the individual packets of Crystal Light with caffeine. Four flavor options. The caffeine gives a decent mid day pickup. Maybe not a 'hydration' mix but does get me drinking more water.
Can also be made for pennies per serving if you buy magnesium citrate and potassium citrate in bulk. I use these plus pink sea salt. The 2lb bags below will last you for YEARS.
Liquid IV or an electrolyte tablet like Hammer Endurolytes. I don’t like Liquid IV while being active (running), but like it at the end of the day, if working outside, etc. I prefer the tablets when being very active.
After a recent, rather arduous 8 day backpacking trip into the Sierra's- with most travel above tree line and temperatures on the warm side, I can say Nuun has been very good to me.
I was putting a Nuun Sport tab every other 16 oz bottle (one straight water, the next water w/ Nuun). Late afternoon I would mix in a Nuun Endurance in the same bottle. In the evening at camp when my buddies were heating water for tea, I also heated water for a Nuun Recovery (you can drink it cold, but was actually pretty good warm!).
Knock on wood, I never suffered a single cramp. I was good about keeping up with my hydration, but as much as I was sweating, I'm sure I was also losing electrolytes.