MIDBOSS ORIN
Read and dodge the first wave. Bomb after the second wave has formed but before the clusterfuck from the first wave reaches you. Second wave will reform; dodge that, and it'll end before the clusterfuck from that reaches you. If you want to do it without bombing... practice the clusterfucks and/or use ReimuB, I guess.
DBDB
Not much here except for getting off the bottom, looking everywhere at once and praying. :V
IN
Keep streaming across the bottom and pick when to change directions carefully. Don't be afraid to use vertical movement if you need to get over your previous stream (although I wouldn't recommend it if you're near the middle rather than the side).
BOWAP
The only thing I can suggest to help you with this is that if a 'wave' goes past and curves back to hit you again, the gaps in the bullets will be in the exact same place (i.e. if you get through a wave and the next set of bullets coming for you is the same wave, stand still). Other than that, read and dodge. I
suppose you could use the safespot, but that takes all the fun out of it and I imagine you want a proper cap. :V