Question

I know there are disputes on this issue, but I’d be happy to know what your personal view is, and also roughly how the positions are divided on the matter. 
In addition, what is said in that Bedtime Shema? From what I understood, in principle the first paragraph is enough and that’s it, but there is also the blessing “Who causes sleep to fall,” and in practice people say more, such as “Lay us down” without the closing formula, which I saw is brought as the custom of the Rosh. If you look at the Tefilon app, you can see that the text there for the Bedtime Shema is really long, so I’d be glad to know whether there is a reason / sources for saying the additional parts (of course, they are not obligatory to the best of my understanding).