Lately I have been a bit busy and soldered all four boards and tested them. There was no problem with any of them so lucky me:). Also I decided that casing for this amplifier will be open type, made of black anodized aluminum.
Bottom side of the board.
On the top side there will be only wires from the board, this also makes easier board stacking.
Hand soldered HLQFP32 package.
Last pic: Only to give you idea how the amplifier will look in the end.