My page sections are around 100-150kb, they are sectioned because my comic is a scroll webtoon style comic but even then the added total for the whole episode would be around 2mb-3mb.
What you can do is while saving click "Save for web" and select the JPEG option when the window pops up, you can control the quality, put it on high or maximum and your file size should be considerably smaller whithout loosing a lot of quality.
Here is an example of a page if you'd like to see the quality, which isn't too bad for JPEG, it's not pixalated or anything.