The most exquisite design can be nullified by bad color choices. It's not rocket science. But there are set principles one needs to learn.
Maintaining contrast in an identity is essential for it to fulfill its primary function: to be easily seen and recognized.
Typography without the constraining flat baselines or top edges allows a beautiful variation for both a traditional or a modern feeling.
Almost any concept for a logo has probably already been used. It is the visual treatment that distinguishes various logos, a system of shapes.
This technique should be applied to every logo design. It is the whole thrust of modern branding design and the common hallmark of the most long-lived logos on the planet.
Negative shapes allow a visual double entendre. If you were working with only the positive shapes, it could come off too contrived, forced or just unclear.
As with any technique, Ligatures, Swashes and Flourishes can beautify, but must never interfere with the legibility of the identity.