I have trouble with some of the cases at times and then there are things like "tekamolo" that you just have to remember.
I've heard that German is one of the hardest languages to learn. I guess that's true
I remembered reading somewhere that Gaelic is the hardest language to learn
Yeah, it most likely depends on what you learned first. I've heard that if you know Spanish, it's easy for you to learn Portuguese since they're similar.
By that, then I think the same would apply to italian too...to some extent.
It could apply to any Romance languages I think
I think for an English speaker it's definitely Mandarin...throwing in a whole new writing system as well.