To cause something is to bring it about. To precipitate something is to accelerate its occurrence, or to bring it about prematurely, hastily, or suddenly. As you might expect, this verb is usually used to talk about undesirable or even perilous outcomes: crises, collapses, disasters, and downfalls are all things that are precipitated. On occasion, you’ll hear it used to discuss swift change that is favorable, but more often than not precipitate connotes a steep downward trajectory.
The terms furthermore and moreover are both transition words, meaning they help connect one idea to another. What's more, they both indicate something additional to what has already been stated. Moreover adds emphasis to the idea that came before it, usually introducing something particular or important (not an afterthought). But neither of these terms is commonly used in speech where shorter, less formal options do the trick.
To improve something is to make it more desirable in some way. To revamp something is to renovate, redo, or revise it. Revamp comes from the verb vamp, which in its earliest uses meant “to repair (a shoe or boot) with a new vamp.” The noun vamp here refers to the portion of a shoe or boot upper that covers the instep and toes. Revamp entered English with its own footprint, but the idea of making something old new remains central to its meaning.