A wise man once told me that the difference between professionals and amateurs is professionals take more pictures and show fewer of them. And that was 30 years ago, before anybody other than the NRO had digital cameras. Your landscapes need foregrounds, unless you intend them to be desktops. Humans are suckers for depth of field. Also motion. Still wheat always loses to blurry wheat.
Make the effort. Remember - photography is the knack of turning perspective into art. Finding foreground is often simply a matter of getting on the ground: As an artist, the object of invoking perspective is to place the audience in the viewpoint you have chosen. When you omit foreground, you are saying "there is something far away, distant and remote from you." When you instead put it up to your feet: You are saying "you stand before a vista. Look." The waterfall images you've got are great. Personal preference only, I only go B&W when the coloration is heinously boring AND the texture really pops. And, if you're going to go B&W, crank the shit out of the contrast in Lightroom so that you can really see it. But that's just my take on it. Anybody can teach you how to take pictures. Nobody can teach you how to take your pictures.
