well, I've spent a lot of time
dying playing on level 4, and after getting used to it, the strategy for scoring remains the same: hope you're lucky enough for the first enemies to survive long enough for you to score well on them, then spend lives being killed by Memory while scoring (since the end of game's bonus give you 100k points per life, you would want to score more than that, and you usually do, once you've studied, practiced and memorized most of the stage enemy waves. Even if you die prematurely sometimes.)
Why did I go back to level 4? Because level 8 doesn't waste bombs as soon as I send shining zako (flaming enemies, or small fry) to their screen (most of the times, even Ran and Mevious will waste their bombs on lvl 4 right at the start :p).. sometimes they don't waste their bombs, but the difference in survivability isn't much.. I'd say, the gap isn't like PoFV Normal vs. Lunatic.. (however, I've felt that the game's difficulty rank or speed may vary suddenly depending on your score, or chains, dunno exactly..)
Perhaps learning how to chain the enemy waves demanded more effort from me, than trying to 1cc this game on lvl 4 with that knowledge.. but would still be easier than trying to 1cc without using it..
I'll do a search for where did I get that info.. (and the videos of the stage enemy patterns)
ebarrett: seeing things like
this makes Kim Do Kesubei look normal :p (not that I would ever see these endings myself, so soon :p)