Well, i don't think i can collect the masochism to do so. Playing through the stage is just a chore and and the lack of windows features makes the entire affair pretty dreadful.
As a lover of the PC 98 games, I must protest. They're quite fun, and certainly not as bad as you're making them out to be. LLS and MS especially feel very much like EoSD do (although you may not like EoSD either). The MS EX stage is all about practise, practise, practise. Streaming the early bullets can net you a lot of points, MS's extra life system requires scoring so you can aim to net a few extra 1ups this way, but the extra stage is really not much different from any other, you'll need lots of practise to get through it without dying/bombing a whole bunch.]
Then there is the streaming spell similar to the one Sanae uses. I hate it. I can't see when it ends because its PC-98 and while i can do it most of the time, its just stressful and feels terrible to play.
This one's even easier to do than her opener since it's all simple streaming, then misdirecting her before moving in the other direction. Actually, I think it's easier than Sanae's, once you get the timing down.
Another attack worthy of complaining about is the one where she shoots a lot of lasers at you and then as the attack progresses fills small bullets within the gaps. That attack sucks sooooooooooo much.
You're jumbling the two separate purple laser phases into one. The first phase is all streaming, just tap to the sides to avoid the fast lasers, then keep tapping through the smaller bullets to avoid the beams.
The second phase where she spams lasers and bullets is one of her harder ones, especially if she fires while moving, so don't be surprised if you have to bomb/die on it, it can take a bit of luck.
Whatever you are supposed to do with the one following it i have no clue about.
While I tend to hide in the bottom corners and weave through the shots, the player in the video I linked stays in the middle with Mima, squeezing through the bullets. If you can get the positioning right, this might be the quickest way to end it.
Oh and the final attack looks like the biggest piece of garbage trash ever. Looks like something that wouldn't really be that hard if it weren't for the garbage flashy background.
It's probably her nastiest attack, and not due to the background. As it progresses, it speeds up, which is what makes it difficult. The only thing you can do about it is reach it with bombs/lives to spare, I've lost track of how many times I died against her while she had a sliver of health left before I finally managed to beat her.
A good video of the boss fight located here.