Reading here about widgets I tried iLauncher and I see that if you have more than a lines worth, the wrap around either trims a launcher icon on the right handed end or hides it completely. This is on my iPad Air 2 and with 9.02, so it may be different on other combinations.
I emailed the author, but no response. So is there anyway to add a line break, which would appear to be the simplest solution? (Btw, adjusting the slider only helps if you have less than a lines worth.)