I recently bought an Apacs Terrific 268. It is pretty flexible even though the specs say medium flex. It 4u and even balance or maybe very slightly head heavy. It is also very cheap for a racket of its quality. So far it seems to be an all-round racket that is quite easy to use.
For Yonex rackets, you can try Nanoray 600 (Flexible racket), Nanoray 700FX (Medium Flexible) and Voltric 60 (Flexible). Please refer to sunriseclick.com website