Pros/Cons of retaining excess water?

I read that water weight varies between 50-70%, which is a bigger range than expected. I typically stay well hydrated but will instantly gain 3-4% of my body weight (5-7 lbs) after a weekend of drinking/salty foods. Back to normal after about 48-72 hrs.

When I've taken creatine in the past, I gain a few lbs of water weight and feel slightly stronger on heavier lifts. This 'slight' improvement seems similar to the effect of being a few lbs heavier after a weekend of drinking/salty foods. For example, I had burgers and beer on Sat evening, gained 5 lbs, and felt stronger at my lunch workout today.

I thought about Fournette's recent combine when he ran a very good 40 at a higher than expected weight, which he claimed was due to water weight. Is there an ideal water weight % for elite athletic performance or is it a case of 'the more the better'?

If it's better to maximize as much as possible (within reason), what are the healthiest ways to increase (i.e. better & more permanent option than burgers/beer)? Is it correct to assume that simply drinking more water won't have as much of an effect as the impact of getting certain minerals out of foods and supplements?