My dad told me that in the U.K. still when he was young they had a very complicated system of recalculating pounds into shillings, pence and guineas. Today I also learnt that in Lübeck in the Middle Ages they had a currency where the different amounts corresponded to each other as 1 Mark lübisch = 16 Schilling = 48 Witten = 192 Pfennige Why where they so complicated? It seems much more straightforward to have 1 pound = 100 pence or something similar.
I can't speak to the historical aspect of your question. But I can comment on whether the systems you've described are actually complex. The Lübeck system is not more complex than any present system. It's just base 4, after the first jump from Mark to Schilling. There are several areas of life in which base 10 is not the norm; in many (such as distance--inches and miles), there's no consistent base. So the currency system you've described is relatively simple, not complex.