Blank or near blank first page
I'm now finding that I can just about cope with full scores, and having non sounding instruments not showing on staves - but able to recover those if I need to edit them on later pages.
One thing I noticed is that often there is a Title on the first page, and then the rest of that is completely blank if the full score approach is used. Is that strictly necessary? Perhaps there are too many staves on the first page to enable them all to be shown - but that seems to still be the case even if the page size is changed.
Should there really be so much blank space on the first page? Obviously it could be used for text or other purposes, but if not it's just wasted space.
Perhaps that explains why some users have "splash" covers with pictures on page one.
Comments
When there are multiple frames/systems on a page, and the last one won't fit on it any more, it is indeed shifted to the next page; regardless of whether it is then small enough to fit on that page or not.
This is very much intentional.
If you don't make staves/system small enough to fit on a page together with the title frame, then yes, it will not fit. And one way to make use of that space is to indeed turn your first page into a cover page, just as it is in print.
It's possible you have a page break on the title frame. It will look like a piece of paper with a dogear. Click on the frame but not on the bottom line and press ctrl+return and it should go away if this is your problem.