Efficiency and size considerations

Basically the performance, download size and memory usage of the project depends entirely on what kind of content you put in your project. See the manual guides on Performance tips, Memory usage and Download size.

In general the same amount of content will have the same amount of download size/memory usage requirement. However in Construct specifically, its memory management loads or unloads entire objects in memory, including all animations and frames. So for example it's better to use multiple Sprite objects (and use Families to share logic) instead of one gigantic sprite that has everything in the game in it: then Construct can only load what you use. But if everything is used anyway, then there's no difference. And there's no point trying to go too far in the opposite direction - trying to make every single animation, or even every single frame, a separate Sprite object is just going to make your life harder for no real benefit. Just use a sensible design and it's probably fine.

Great, thanks for the detailed and prompt response!