Well, it is expected that at first only around 20 people will get the magic waiver and even then it requires a special permission to make a mage character. But for the chance that you do eventually achieve it, I will give my views.

• If they are old it's best to make one that is just starting to age because they can only live for 20 years longer after they start, if not less. But this would also mean a long backstory because they've lived for at max 180 years before starting to age.
• If it does end up being a dwarf they will most likely end up being very fat due to their strong body-type. Just thought I'd point that out. The only problem with Ailor is that Expert forms can take over 100 years to learn so if you want a really experienced one I would go for Altalar, or any other Elven race you find suitable.
• Well if you do decide to use that type of clothing it probably shouldn't have anything like jewels or anything too expensive unless you have a good backstory to explain how they got it. Also dyes can be very expensive and I thought it should be something to consider. You should at least know Purple is the hardest to get.
• Nothing wrong with that at all, I would go with one that is generally untrusting but also tolerant. As kinder ones would be more unlikely with all the hate towards them.
• You don't really choose one type, but you could choose to only learn one area of spell. There won't really be a specific type of mage anymore but different spells you could learn. And I don't know anything about the spells other than what categories there will be so I can't really suggest anything yet.

Also you should make sure you are relatively experienced/good at roleplay. The people who play Mages should generally be experienced and  have a good understanding of the lore. Good luck!