These are mesmerizing! Very professional, and that's coming from a filmmaker/video producer myself.
If you really want to grow this into a self-sustaining channel, my one suggestion would be to use music and rhythm more to your advantage. Right now the pieces come in rat-a-tat-a-tat-a-tat-a-tat which is cool, but fatiguing on the senses, and the music has a sameness throughout that doesn't necessarily match the set that we're watching. I found myself scrubbing ahead to other parts of the video just to see what else was going on, and any given moment was pretty much the same as any other given moment. Like Lego-building itself, it can get a little monotonous.
I'd find some royalty-free music that matches the tone of the set itself and then mix up the speed at which your pieces appear to go along with the music. Some ragtime to go with a train set, crashing nautical anthem for a big boat, something out of Fantasia for a Friends build, etc.
As an example, say you were building the SSD and wanted to use the Imperial March (yeah, I know you should stay away from copyrighted music, but I'm just picking something everyone is familiar with.) The opening BUM-BUM-BUM could show some of the big plates appearing in staccato fashion, then the bah-diddle-diddle part has little pieces zipping in to go with the quick strings.
Just a suggestion. It's cool as it is now, but really making it into performance will kick it up to the next level. Either way, nice work!