Yes, it is high time Link's moveset was expanded. It is highly probably the Master Sword is an "arming sword", judging by size and length, and considering the rough era in which Hyrule is placed. (
http://en.wikipedia.org/wiki/Arming_sword). An arming sword was primarily used with a small shield or buckler, much akin to the Hyrule Shield.
The arming sword had excellent balance, and was used for three things - the parry, the cut, and the thrust. The parry came in three varieties - a horizontal parry would block in coming vertical cuts, the vertical parry would block incoming horizontal cuts, and the flick parry would knock back the tip of an approaching thrust. The cut came in two varieties, the horizontal, and the vertical. The thrust was a single type of move, however, one could thrust. and yet if stopped, continue sliding the blade until the crossguards locked, before physically overpowering an oppponent.
The shield could be used to deflect blows, allowing for a quick strike, and also as a "metal fist" - smashing your opponent with a shield would cause massive damage.
I think Link's moveset could be expanded to:
A basic horizontal strike, which could be repeated up to twice more for a three hit combo.
A basic vertical strike, which could be repeated up to twice more for a three hit combo.
A thrust, which would cause high damage, but leaves Link open to attack.
A vertical parry, which stops incoming horizontal attacks.
A horizontal parry, which stops incoming horizontal attacks.
A sword flick, which knocks away incoming thrusts.
A shield block, which knocks away all attacks, but Link cannot immediately attack afterwards.
These would then have more powerful versions:
A spin strike, a powerful spinning horizontal attack, which can cause massive damage, but leaves Link open to attack.
A jump strike, a powerful juming vertical attack, which can cause massive damage, but leaves Link open to attack.
An ending blow, a powerful jumping thrust, which will kill most floored opponents instantly.
A shield attack, where Link thrusts with his shield, knocking back projectiles and stunning most enemies.
Finally, the most powerful series of moves:
A Great Spin, where Link spins horizontally, causing massive damage.
A Charged Jump Strike, where Link leaps and slashes vertically as hard as he can.
A Helm Splitter, where Link does a three hit combo on a shield stunned opponent.
There would also be a few techniques that depend on certain other objectives:
Back Slice: Roll and attack at the same time.
Mortal Draw: Draw your sword and attack at the same time.
Dash Attack: Dash and attack at the same time.
Finally, the sword beams:
Sword Beam: If Link is at full health, he can launch a beam from his sword.
Peril Beam: If Link has one heart or less left, he can launch a beam from his sword.