Just got Normal 1cc, I actually have stuff to say now.
The formations are insanely strong, great damage + range + defense. Horizontal line is good general-purpose. I don't use the L beam that much but it probably has utility somewhere since you can set it up in 4 directions.
Phoenix is absurd, if you are having trouble with certain sections then try to get it beforehand. Good for any boss/midboss and the stage 7 laser hallway.
Use slowmo to dodge, it is expected of you. The electricity beam between your ships deletes most bullets, make use of this to clear out nasty patterns. (Also applies to formation)
Absolutely recommend reading the article Birdman posted, playing for score doesn't hurt your survivability that much and can net you at least 3 extra extends. Caravan mode is a good way to practice this and is super fun in its own right.
One weird trick is that you can carry a formation chip from the end of one level into the next. Juggle it for a while and watch the HUD, then pick it up once you see your formations reset. This makes certain beginning sections a lot smoother.
This game is actually kinda glitchy, I've had one trigger multiple times that gets you stuck in slowmo until you lose a ship, and another that prevents your ships from following you in slowmo. Very odd.
I'll try for a Hard 1cc, from what I saw the patterns are a lot meatier.