Ok, well... this seems to be very active discussion. Excellent. I won't try to respond to all of the particular points, but, judging from the way people have been talking, especially with such interest in playing Shinigami, it looks like I'm leaning towards the mid-level game, now, though I may end up running the low level as a smaller, more free-form game. I've only received one finished character, so far, but that's fine.
One thing I do want to point out is that, frequently, battles will be taking places in different areas; unlike D&D, which assumes a party vs. a monster or two, this will, akin to the series, focus more on 1v1 or 2v1 fights... or, as we advance, more likely 1 versus many Hollows, given their cannon fodder capabilities. =P Thus, in the majority of cases, player balance isn't as important, because all players will contribute to their own fights.
On that note, yes, the Quincy's getting a revamp. Make the following changes, and see how they work:
Raise HD to d6; remove Human Body flaw, maximize all HD.
Raise attack bonus progression to Fighter levels. Adjust Defense bonus to reflect this, as the warrior Shinigami.
Double current range. Increase damage to 1d10 at 6th level, improve again to 2d6 at 9th, 2d8 at 13th, and 2d10 at 17th.
Add a bonus feat at 4th level, and every 4th after that; when you normally add attribute points.
Revamp the entire charge mechanic; triple the maximum held charge (with no concentration check), gain charge each round you are engaged in battle, equal to the amount you would gain by charging as a move action. Gain an additional charge for each ally, actively engaged in a fight, within 40 feet. You cannot use actions to gain additional charge, though it should no longer be needed.
Gain an automatic enhancement bonus to your bow equal every four levels, starting at 3.
As a full round action, starting at 5th level, the Qunicy may fire a single, incredibly powerful arrow, imbuing it with spirit charges. Unlike the normal enhancement mechanism, all points spent increase the damage by two, but for every two points spent, take a penalty on the attack roll of one. (This is basically a very powerful Power Attack, though it requires a full round for a single attack.)
Halve the cost of the Hirenyaku.
At 8th level, Quincy gain the ability Force of Will, and add their Charisma modifier as a bonus to damage to all shots.
Change the power of the longbow; it's silly. A flat +2 to damage, and +20 range. The crossbow adds an additional +1 damage to all shots, on top of the die increase.
I think that ought to cover it. At least, make them a much, much more powerful force, as they should be. Ishida was sniping Hollows in the first episode he appeared in, not plinking them to death, one at a time, charging for a minute between each Hollow. =P
And yes, I love Yourichi... a nice sense of humor, too, with her transformation.
A few notes on character introductions; Shinigami will begin as a member of the 13 squads, your choice. The campaign, in the real world, will take place in some town in Japan. Equipment will be assigned to the players, as appropriate; there isn't much in the way of 'magic items', anyway.
I was surprised at a few of the choices made by the author of this as to what characters were what classes; Rukia is listed as an Expert, not a Spellcaster, though she has numerous meta-magic feats, and always felt very fragile and kidou focused in the series. Meanwhile, Matsumoto, who struck me as an Expert, is a Warrior, though Byakuya is, appropriately, an Expert. It really comes down to a matter of player preference; all are equally viable.
All in all, I have high hopes for this idea; I plan to work with you guys, make sure that everything remains fun for everyone... that's the point of all of this, ain't it?