I usually play 4* maps(and 4.5-5.5 * when pp farming), now I can S any jumpstream maps under 4* and my jack is ok. However, my speed and tech is poor so they are always a drag on me when I'm challenging dans(I've passed 4th dan, by the way). What's worse, my fingers are so easy to be tired out that I have to pause when playing most stamina maps(I play with my wrists up an I think it's less tiring than wrists-down). So can you give me any suggestions or recommend some maps to practice? And how to improve my stamina?