Theres a lot of delays with Hitsugaya shikai... strat to defeating his shikai is just dodge 1 ice dragon and then tear into him becuz all he can do is melee attack... cant use kidous or anything until the first ice dragon is about to dissappear. Tho I probably shouldnt be telling you guys that! xD
I got Bankai this last friday, and im lvl 235 now and STILL havent mastered Bankai... such a pain... im close tho, it only drains like 400 reiatsu a second... but still it took me 3 days to get it to where its at. Not sure how long it takes for other to master their Bankai tho.
There is a bug or bad coding with Hitsu bankai attack... You can attack through walls with it

should probably fix that.