First off, the Arcadian Hippogriff cannot benefit from the +4 attack of the Hot7W nor the +20 damage boost since it is a "magical beast" rather than a "beast".

With respect to riders, if you really wanted to, you could get Tordek up to auto-hitting AC34 with a flank - even in 200 points.  You can get him up to 36 if you felt like it with the Militia Archer who could give him another +2 to attack against anything high enough level to even comes close to AC that high.  Since he has cleave, he can often make two attacks a round as well.  The amount of damage isn't quite as high, but he's also quite a bit sturdier.  If you're serious about playing the Hippogriff in Epic then you'll have to worry about keeping it alive.  Dual Cyclones (and many other builds) will kill it before it has a chance to do anything.

I do think, however, that this piece will see some play if the Vintage format takes off.

I agree. And maybe, i want to say this: if moderator of this forum have the opportunity to suggest changes in WoTC, he would express something related to this item, because just for the fact that in major tournaments (like in Netherland) magical beast aren´t considered beasts it doesn´t means that could be comprehensive for the rest of countries in the world.

It must be clarified in an errata. All the things that you don´t write doesn´t exist!!!!

However. Aplying that concept: "beasts are different from magical beasts", i modified my warband.

What is my point? Using a low cost miniature or maybe two, Arcadian Hipogriff, have the chance to destroy a higher cost Miniature just like Doresain, VID, Cyclone, Fire Titan Rider, having the rest of your warband reserved for a prolongated melee skirmish.

This is the new warband:

Arcadian Hipogriff x 2
Tomebound Arcanist x 1
Drizzt, Drow Ranger x 1
Runecarver Eidolon x 1
Storm Silverhand x 1
Wild Elf Warsinger x 1
Ryld Argith x 1
Human Cleric of Bahamut x 1
Mercenary General x 1
Militia Archer x 1 (Free)

Map... Blue Dragon lairs, Tomb of Peregrin Queen or another open map.

The Strategy... the same explained before... maybe a double area attack trying to confuse some miniatures to neutralize potential attacks. Then, Arcadian, without rolling dice make a lot of damage and so on.