Personality doesn't have much use unless you plan to use the streetwise or etiquette skills. I always like to keep it at at least a respectable number though so people will still talk to me..
Willpower modifies your resistance to magic. A lower WIL means you may occasionally go down quicker against a spellcaster who has a powerful spell.
Luck modifies everything you do (in a small way). It also modifies random loot you find, as well. I've found it's not really necessary to dump a lot of points into it. Personally, in your build, I would rather keep LUC down to around 50 and boost WIL back up to 50 as well so that you have a better resistance to magic. WIL isn't generally something you're going to pour alot of points into when you level up, so it's better to keep it at a decent number to start with.
The only disadvantages that you may really notice will be (obviously) lower magic ability in daylight--not a huge deal--and the critical weakness to disease. I remember taking this and getting diseased in Privateer's Hold from the rats. It can add a fun challenge, though. (and you can create a nice backstory as well--growing up as a sickly child or something like that)
There's really no point in including Medical or Streetwise in any skill slot, even minor. Medical will develop on it's own, as the skill is checked (and therefore trained) every time you sleep and heal.
If you're going to completely fill your Major Skills with magic skills, you may want to think about adding more INT off the bat.
All in all though it's a pretty solid character. The nice thing about Daggerfall though is that unless you completely fudge things by putting languages in your major skills and lower your END to 10, you can usually get by pretty well regardless.