Heavenly Sun and Harmony and Lovely have similar endings, but the difference is that for Heavenly Sun, you just need to maintain life over 80% through the end since the beginning is easy; for H&L, you need to build to 80% after the drumroll (at least that's how it is for me, I typically hit 2% near the end of the drumroll), so that's why H&L is rated higher.
Also since it can't be said enough GOB:WS is like the hardest shit ever for a 10.
I definitely agree there. Still I'm puzzled as to why my previous attempts of hard clearing Heavenly Sun [a] all ended up in failure when the only hard part is in the ending. It's not the same as hard clearing Zenuis-I-Vanisher [a] where the hard parts are centered on the middle portion.
Also, in the case of H&L [a], yup it's the drumroll (with alternating chords) that usually wipes me out as well with only genocide clearing being the only way for me to clear it.
In the case of GOB(WS), I haven't seen its another chart but I can tell you that its hyper chart is already quite a challenge for me when I was still a new at this game (started out with 7th style PS2). I still don't know as to how well I can do in that song (since I've never played it in the arcade for months now).......
Either way, the scratch sounds of that song are still cool
answer to topic title question: if you plan on having fun, yes.
Well this answers depends on the person's preferences and priorities.
For instance, in my case, I can't clear any level 12s yet (been playing for five years now). Does that mean I'm not having fun? Of course not. Sure I want to aim higher but right now, I enjoy where I am right now.
So my verdict on this:
You don't need to pass level 10 stuff to enjoy this game
But as long as you keep playing, eventually the level 9 stuff will seem easier and the level 10 stuff will be passable.
Well yeah, that's basically how players progress. Existing stuff becomes easier and newer & harder stuff becomes more passable (directly proportional to the amount of time and effort spent).
All I'm saying is that if it's all for the sake of pleasure and enjoyment, then one does not "NEED" to pass a certain difficulty of songs in order to achieve this.
It's an added benefit but definitely NOT a 'requirement' for one to have fun in BM IIDX.