In my point of view, I guess Form 6 is much preferable than A-Level. Much is needed for financing the A- Level whereas Form 6 doesn't need much. Since the Science streams also offers Sciences in English, it wouldn't be difficult at all.
Furthermore, PA helps the students to maintain their BM which is rather useful too. Other than that, there's MUET which is really helpful in the sense that the students get to improve their English.
Apart from that, students have more time with their families before they go further for their tertiary studies. I would actually encourage my kids to do Form 6.