For me I would recommend metal construction toy Meccano Set/erector sets. I have few reasons below.
Engineering Focus: Meccano Sets & Erector Sets use of metal parts and the inclusion of tools provide a more engineering-oriented experience. Building with nuts, bolts, and plates allows users to create intricate structures and mechanical models, fostering a deeper understanding of engineering principles.
Mechanical Complexity: Meccano sets & Erector Sets are known for their mechanical complexity, often featuring gears and moving parts. This adds an extra layer of engagement and learning, making it appealing to those interested in the mechanics behind the structures they build.
Versatility: Meccano Sets & Erector Sets versatility extends to the ability to construct models with functional components, offering a broader range of building possibilities. This may be particularly appealing to individuals looking for a more dynamic and interactive building experience.