Alt - new character or same ?

I was wondering if you want to make a second job, is it better if you make a totally new character or use the same one ?

1. If you make the same, you can use the same tomes/phil/myth cap for your alt, while you earn them on your main. This will speed gearup of the alt.
2. If you make the same, you cannot join as PLD on coil for example and roll for WHM gear, so is not helping that way
3. If you make the same, you are saved in T4 coil, you cannot do T1 again with your WHM so you have to select if you wanna do this week coil with PLD or WHM.

So generally speaking, which one is better as idea ?

I have made an alternate character. Working out pretty well so far considering how many lock outs we have. One I finish with one character I play the other.

Only downside is leveling up the classes to jobs. God thing I took care of that in 1.0 :3

I recommend using the same character. Circumventing the mythology cap and being able to do more coil groups are the only advantages to having a new character. By using the same character, you have the armory bonus to help level things up, easier access to cross-class abilities (Unless you plan to do a LOT of leveling), and can work on gearing up other classes while doing other content (For example, if you see a garuda sword drop, but you're on your WHM, or using philosophy tomestones you get while farming myth to get darklight), as well as having the ability to share gear such as accessories, or just about any tanking/healing/casting gear.

Another thing to keep in mind: There's not much need to rush to get everything on everything ASAP. If you're only working on one job per character, it shouldn't take THAT long to get all 90+ gear. Then what?