2. Somehow when I exit insert mode, the trailing space after my text gets deleted

Have a look at the variable evil-move-cursor-back and evil-move-beyond-eol. May be this could help you.

I am looking for something similar, I also do my edits in the left window, if I open a read-only buffer (man page, help, helpfull, info …) I would prefer it will always open on the right side. I can’t help you, but I hope someone else can.