The objective of this study is iterative systems based on general types of curves, not only on circumference arcs. We begin by presenting some implementations and generalizations of constructions based on arcs of circumference. Then we consider constructions based on general curves and give a “universal property” relating to the primary construction that exploits arcs of circumference. With the prospect of applying these theoretical models also to coastal geomorphology in the future, and inspired by one of the best-known models on the subject, the logarithmic spiral one for the so-called headland-bay beaches (HBBs), we study geometrically some cases in which the constructions are based on arcs of the golden spiral. Simultaneously we concretely illustrate and explain the universal property above. Finally we dedicate a section to discuss the possibility of how to numerically evaluate and compare the (infinite) lengths originating from our theoretical geometric constructions. Some explicit examples, calculations and comparisons will be provided by the use of infinity computing which is one of the various possible assets that contemporary non-standard mathematics makes available.