First of all, I’m so glad you bring up the Lego Movie in a shading and lighting class – that movie has some of the most GLORIOUS shading and lighting! I almost had a hard time paying attention to the narrative in light of the S&L 😅
I like that you changed up the HDRI for the toy truck scene. Totally shifts the mood. The yellow is blowing out a bit much; kinda feels like it’s glowing. But the yellow, grey, and black read very much like plastic.
To echo the other feedback, my biggest note on the arch viz renders is the lack of color. White-only / highly desaturated lighting is generally uninteresting, especially when there’s no real materials in the scene (clay render) like this one. I strongly recommend implementing stronger colors: Yellow orange for sunlight, blue shadows during day time (from the sky), warm orangy-yellow for lamp lights and purply-blue for moonlight.
Besides the color, it’s pretty good in terms of values. The black window is probably from Blender rendering an alpha channel by default but it’s fairly distracting in the daytime render. A landscape texture is best but even a blown-out white will do.