He is actually insanely powerful. But his difficulty of use is the balancing factor. Plus no Akira user is actually using him to his full potential so... no he's not really an issue lol. People just suck.
Its actually impossible to use Akira t his fullest potential. How many Akira users do you see do Full DMG or Guarantee Combos? Or even the Swrod Style: Eight God Point Harmony?
But couldn't that be said about a lot of characters? Not everyone uses their characters to their fullest. Everyone makes plenty of mistakes. I suppose people can get close to full potential, but they'll never really get there.
Wrong again Hachi. @Tenryuga uses Ein to the fullest and @iHajinShinobi uses Ayane to her fullest and @Timasty uses Pai and @AkaShocka uses Sarah to the fullest. However they don't use any unnecessary techniques
Ten uses Ein as the character is meant to be used but could still strive to improve. Hajin is probably the most on point Ayane I've seen but as he said himself there's still more to improve on.