Oh, and need more scoring tips.
General tips after watching your run:
When killing bosses, try to time their death when their's the most bullets on the screen. It looks like you try to do this in the beginning but then forget about it later on. It helps to be familiar with the patterns so you're comfortable waiting for the screen to fill up.
It's kind of hard when they're unexpected, but try to maximize the value of your deaths. After you die you're invincible for a few seconds, so use that time to graze and position yourself optimally. Also think about when the best time to get to Max Power would be - you don't want to stay underpowered for too long since you won't be able to POC, but sometimes it's worth it to wait until there's a ton of bullets on the screen before powering to max, since then you'll cancel those bullets for star points.
When you bomb or die on a spellcard or non-spell, wait a little bit for the screen to fill up with bullets again before killing the boss.
Some stage specific stuff:
Stage 1 - your goal should be to collect as much power ups as possible. Ideally you'll have at minimum 70 power before the boss.
Stage 2 - Try to have or be close to Max Power by the midboss so you can take full benefit of all the popcorn enemies afterwards. Until you're at Max, collecting power ups should be prioritized more than point cards (although try to collect those as high as you can too). Also, Cirno's first non-spell has a safespot which really isn't that hard to use.
Stage 3 - Practice milking Meiling's 1st spellcard. That part is really important.
Stage 4 - When grazing the hairballs at the beginning of the stage, don't shoot. If you don't kill them then they can shoot more bullets for you to graze. For the part with the books and lasers (after the midboss), start near the edge of the screen so that as soon as the books appear you can kill one of them. Then move towards the center and try to work your way up to the POC. For the bullet-cancelling fairies after that, wait a bit for the other enemies to fill the screen with bullets before killing the fairies. For the last part of the stage (with the three fairies), the easiest way to do that without bombing is to damage the middle fairy without killing it, then start attacking the left (or right) fairy just as the hairballs come in. Then you can work your way to the other end of the screen, using the time between when the fairies die and cancel the bullets to line yourself in front of the next fairy. You'll make more points that way too.
Stage 5 - Unless you really think you'll need your bombs for survival, it's a good idea to use a couple in the first half of the stage to be able to safely kill all of the enemies and collect point cards above the POC. Also learn to milk midboss Sakuya's non-spell - it's really easy and nets you about 2000+ graze. That alone will boost your stage 5 score by a lot.
Stage 6 - Pay attention to how many bombs you have
Also for the safespot on midboss Sakuya, try to stay close to her during her non-spell. That'll give you more time to adjust yourself when the spellcard starts. You should practice this part as much as you can - it's really frustrating to do perfect on stages 1-5 and then die here.
If you watch high-level replays you can find other tricks you can do to boost your graze and collect star points. A lot of them will require using your bombs and suiciding to boost score - you'll need to decide for yourself how many of your lives and bombs you're willing to spend to boost your score while being confident that you can 1CC the game. I think the stuff I wrote above though are the most basic and easiest things to work on, and will net you a good improvement.
