Okay I'm no expert so I'll call this a GD, but I thought I'd document the basic rank/scoring systems of PS2 Arrange/Black Label. Anything I say with regards to scoring is only what I've found to be useful for me so far, so don't take it as the final word.
General differences between OG Ibara and Black Label
Extends are given out every 10 million (as opposed to 1 million in OG Ibara).
You receive 1 full bomb upon dying (as opposed to 1/2 a bomb in OG Ibara)
The ship's hitbox is smaller, standard Cave size.
Holding the fire button slows your movement, and significantly increases the firing speed of the main shot.
Sub-weapons are selectable once collected, and fire from all three options.
Option formations are selectable, you can choose from Normal, Back, Wide, Rolling (spinning), and Search (lock-on).
Ship Types
For the differences between ship types, refer to Icarus's last post in
this thread. The lists retain the A,B,C,D order of the PS2 menu. The only difference is that option control is of less consequence in Black Label because of selectable formations. For reference, here is how the ships' speed
compare to each other.
P1 Type D [Fast]
P1 Type C
P1 Type A
P1 Type B -\ These two have
P2 Type D -/ identical speed
P2 Type C
P2 Type A
P2 Type B [Slow]
I've been using P2 Type D, and sometimes P1 Type D because I like their bomb for catching patterns, and P2 Type D is as slow as I can handle while still being able to chain medals for the most part. I haven't really experimented with the other ships, so post and let us know what you think about the other ship/bomb types.
Rank system
In Black Label, rank can increase much, much faster than in OG Ibara, and can decrease just as quickly. Collecting powerups, bomb fragments, sub-weapons, and medals will increase rank. Powerups and bomb fragments add a small amount, while sub-weapons add a bit more. Medals increase rank based on how much they are worth; a 100-point medal will add none (or almost none), while a 10,000-point medal will add 10~15%. Destroying parts of bosses increases rank significantly. Survival time and using stronger sub-weapons may increase rank, but it is a completely insignificant amount if they do. Collecting roses decreases rank, and dying resets rank to 0.
Scoring system
The central scoring system in Black Label revolves around the multiplier (up to x300 for max rank) applied when you cancel bullets into roses by bombing. The roses in turn decrease your rank and the cycle starts over. So you should try and increase your rank as quickly as possible, then wait for a big pattern to cash in on your x300 multiplier. Medal chaining still exists, and it is still very important for scoring. Not because of the points they are worth, but because of the rank they are worth. The higher level
medals you can collect -> the faster your rank will recharge -> the more often you can cash in on a big multiplier. Destroying bosses/boss parts and certain enemies/buildings will also trigger all on screen bullets to be canceled into roses. For example, all the big square white factories in stage 1, or the beige tanks in stage 2. It's important to learn which things trigger it, since it's a free fullscreen cancel and you can save your bombs.
It's really all about the multiplier. If you have a high multiplier, but you bomb a not-so-juicy bullet pattern, it's still worth it for the most part. You won't cancel that many bullets, which means your rank won't go so far down, which means you'll soon have a high multiplier again. The only downside is that you wasted a bombing opportunity. But if you bomb a big pattern with 0/low rank, it really doesn't matter how many bullets you canceled, at x1 it's simply insignificant. Though the only time there are usually big patterns with low rank are boss fights.
In-stage rose triggers/scoring opportunities
Stage 1 - White factories (they always appear beside or close to the cranes with rocket launchers). When bombed, they will spawn a large number of medals (12 I think). I usually use these to max my rank right before the last factory on the right, then destroy it to cancel the last enemy swarm before the boss. Optimally you can end up with about 5 million before the boss, and 6.5 entering stage 2, though usually I end up with around 5 million after the boss.
Stage 2 - Beige tanks. These have 2 forms, the first fires straight rockets, then when the uns are destroyed they will fire a simple ball pattern. There is a point where there are falmethrowers on each side, with a tank in the middle. It seems a bit tough to destroy the tank early enough to catch both flames without risk. A better idea seems to be destroy the tank's guns, then destroy each flamethrower's first form. They will start shooting the ball/spread pattern from behind you and you can destory the tank then. You can get a lot out of the flamethrower pattern, but it takes a little finesse. You can alternately bomb the pattern with two turrets (one in the middle shooting twin sets of 3 rockets and one shooting a ball pattern) that comes just before it. The last pattern before the boss is also a big scoring opportunity. There are mechs on the left, railroad turrets on the right, and a twin rocket turret in the center above them. There are also two turrets on each side of that which will come into view a little into the pattern which should fall into your bomb.
That's it for now, have fun shooting stuff.