Oddly enough I found the Duplo line much more fun to play with as our kid went through the blocks years. You could build something substantial with fewer block clicks, there were fewer different types of blocks, they were less fiddly and prone to vanishing into rugs/carpets, etc. Also the proper Legos tended to be sets which makes it very stressful to mix them into a misc bag.

Duplo is also compatible with regular Lego. We used Duplo for the big structure and Lego on top for details. Great way to build huge stuff quickly.

https://upload.wikimedia.org/wikipedia/commons/0/04/LEGO-kom...