[ArchonShiva]

For the issue of characters possessing incomplete umbrellas, I suggest making specialization free, as Ars Magica did:

For each skill¥, pick one aspect that you're especially good at (+1). You can also save o e point on final cost by picking an aspect you're especially bad at (-2).

This could be tweaked, but I recall that having a specialization on every skill greatly improved initial flavor, but also helped players memorize the tasks within each skill.