After the patch me and my friends were partying, me as ARC and they were LNC and PUG. I kept being KO'd because I took hate too quickly, 2/3 deaths in and I started letting them take hate initially for 10-15seconds, they would get a bit of DPS in and a Taunt or what have you, then I would quelling shot, shoot and gradually getting up to be able to WS. It's not rocket science, it's trial and error after a patch.
I am not entirely 100% behind it though, I do think that Cure's could come down a little bit in cost and enmity spike; only a little. I certainly do not want to dumb down play too much, but making it a little easier on people wouldn't hurt IMHO. You can say 'You're a bad player because you can't tank post-patch' but the game shouldn't be too harsh that the masses can't do it (even if the masses are idiots, I will reserve judgement of that for now). Nobody wants to do a /shout party and the guy can't tank because he hasn't bothered to level CON. If SE ever make the search functionality more transparent, this could be frustrating.
I guess I shouldn't speak to harshly about this as I have not tanked myself yet so I can't formulate a complete opinion.
I am split on my opinion of ranking up other classes to supplement your 'main'. Yes this makes for great customisation of a class and is a really cool idea, but I see what people mean when they are ranking up a mage class so they have effective abilities to be able to tank as Gladiator. But I suppose this was like leveling up a sub job (as someone mentioned). We are still in-between patches so I will probably formulate a more structured opinion once I see a concrete direction for 1.19/1.20
How relevant will leveling up other classes be when jobs hit? Who knows. My personal preference would be any job for any class and if you don't play/chose them optimally that's your fault however, my gut feeling is that it will be something like GLA can unlock PLD or WAR. CON can unlock RDM or WHM. This would give your class some diversity but still keeping it limited.
Sorry if my opinions are all over the place, I just wanted to put out my positive/negative thoughts in a hopefully reasonable way.