I do occasionally ask newer employees who are not experienced with code reviews to split up a review into multiple smaller reviews. Actually there is a natural equilibrium that happens here. There is an exponential relationship between complexity and size of a single change and review latency, just because that's most efficient for reviewers (assuming some hard limit on acceptable latency as well). Most changes take on a uniform medium size as a result of this. The sheer number of changes isn't as big a factor here because most reviewers look at reviews in batch anyway.
Separately, minimizing diffs with the codebase is not just easier for the reviewer, it also makes 'blame' and resolving problems with existing code easier. You shouldn't break your back to minimize diffs, but as a form of hygiene it is not without merit.
Your definition of continuous integration is interesting in that I haven't seen it used in that way, or rather with that emphasis. Smaller syncs-to-master than "this is the entire feature" are great, but their effectiveness depends on automated testing, building, and deploying. When code under review is a coherent, high-quality, and tested thing, this can be a boon for CI because you get a small chunk with clear before and after states, which you might not get from just winging it. You can also work on code while other code is under review, especially with a Scrum/Kanban-type task system.