If you are engraving (or printing on, etc) the frame, then I think "Forever and Always" will be nice. Please be sure to capitalize "Always" but not "and".
If you are writing it by hand, then I feel like it is a more personal message. In this case, I think "All the best for your future" is more appropriate.
In the case of a hand-written message, it should convey your wishes to the other person(s). If "Forever and Always" is written by hand, it could connote a different meaning than you intend.