Please let me play multiple classes.

[Ryios]

Square Enix does not want people who play 40 hours a week to have full iLv90 for all jobs before the next patch while others who play 10 hrs a week has only geared 1 job.

But you already can. Just create another character for your next 50. Knock out the quests and dungeons with FC help and your 50 in < 1 week. Then you farm 300 myth on two jobs every week and have two jobs in full IL90 in 3 months. If you did that from launch you already have 2+ characters in mostly IL90. And this is what a lot of people are doing, which makes the games single char system seem like a waste.

If a path exists around a limitation players will take it.

[Zfz]

And this is what a lot of people are doing, which makes the games single char system seem like a waste.

Not at all. For a lot of people it saves a lot of time to be able to level up a new class/job in the future and immediately have gear/items ready from GREED rolls or from left-over loot. It also means if I'm not satisfied playing my current main, I don't have to throw all that time I invested away, the crafting/gathering levels I have accumulated, etc.

Just because it doesn't serve one purpose, doesn't make it a complete waste.