How easy are "easy" languages?

I don't mean closely related languages, but, for example, people say Indonesian is very easy, even thought it is quite different (but still has ton of western influence), but how easy are simple, lingua fraca like languages to learn? swahili is another that comes to mind and has a similar history to malay/indonesian.

Edit: just don't reply anymore if you are going to say something obvious, please. I'm on my fourth language, I KNOW just like I implied on THE VERY FUCKING 1st LINE that the closer to the first language the better, I KNOW EVERY LANGUAGE IS DIFFICULT, specially for you americans that only have to learn half a language to go throught life. I thought I would find at least over 2 digits iq here as a rule, but i guess it's even worse than the average sub. AND FUCKING READ THE POST FOR GODS SAKE