I am wanting to know is there a standard size that "Professionals" save their pictures at? And if so what is the best way to save images?

I have a number of export presets set up in Lightroom for the different sizes, quality and with or without watermark. I'm trying to understand what the best way to go about saving images is. Currently I'm keeping 1920x1080 at 72dpi as a jpg and saving original at 3001x1688 at 300dpi as tif. I'm also thinking about saving the original raw file too.

I tend to crop the majority at 16:9 but don't know if if there is a standard size or sizes the experts use.