You own an open A and an open D, and probably the assumption that comes with them: a more interesting sound needs more shapes. Hold the A still instead and walk one voice down inside it — A, G♯, G, F♯, F. A whole progression falls out: A → Amaj7 → A7 → D → Dm, back to A. That sliding voice is the slippery slope, and it has a name: line cliché, or CESH. The Rhythm part explains it properly.
This is one arrangement, not three études. All three parts are the same piece — A major, ♩ = 70, standard tuning, no capo — with the same five-bar form and the chord changes landing in the same places. What changes is density: full chords, then partial chords, then single notes. Two of the five chords sit outside A major: A7's G♮ and Dm's F♮ are the colors that make the slope work. The same five falling notes run through all three parts; each puts them on a different string.
Rhythm. The loop as full open chords over one unchanging strumming pattern, where most changes are a single finger moving one fret.
Triads. The same progression as three-string triads, with one string walking down five frets in a row while the other two hold still inside each chord family.
Lead. The same progression as single notes, a palm-muted riff whose opening bars answer a falling note with a fixed one, so the harmony moves without the riff changing shape.
The order is Rhythm → Triads → Lead, but it isn't a straight climb. Rhythm is the easiest. Triads asks the most of your fretting hand, and Lead is Intermediate and the hardest. Work straight through, or take whichever part fits your week.
