In my opinion, FL Studio is the easiest of all to learn, creating melodies, loops it is extremely easy and fast, general interface is very friendly to everyone, but if you wants to go to a different DAW is more troublesome. Is easier to go for example, from cubase/ableton to logic, than from FL to Logic. I remember when I started with fl, learn the interface and generally most of the features, took me about a few days, less than a week. For comparison, when i learned Cubase, i spent a month on it.
One of the disadvantages of FL in the opinion of many people is sound quality worse than in other programs. But is a myth, the fact is that the fl studio takes most of the computer resources than others daw's. and need a good sound card.
if you have a Mac, no problem, there is also Mac version of FL Studio.
and finally, the most important are your skills, you can create a great track regardless of what program you use to, so if you work comfortably in fl, stick with it