The Eagles were a very useful design.
They were modular, meaning repairs and modifications could be performed fairly easily. Their skycrane configuration also allowed them to carry a wide assortment of large payloads to any location on the moon or to NEOs. Another reason to build them is that they just looked really cool. One modification I would do is to replace the four chemical combustion main engines with two nuclear thermal engines. This would make them safer and more reliable as well as allow them to use a wide assortment of propellants without the need for added oxidizer tanks and plumbing.