I don't have a whole lot to add to this topic that hasn't already been said.
I use Toujeo, and it also can burn more than my other insulin. I inject both Toujeo and Novorapid into my belly, but I'm also fat and have a lot of belly, so there hasn't been a need to inject elsewhere (yet).
One thing I do is lightly touch the needle to my skin. If it already hurts on top of the skin, I know I'll hit a nerve. If it doesn't hurt on the skin, 9 out of 10 times it doesn't hurt nor burn (as bad) when I inject. I don't know if this is because of my weight or not, but it's not uncommon for me to touch my belly with the needle in 5 different places before I find a spot that doesn't hurt.