You know, the eldritch knight goes a long way to getting the flavor of Strahd, but I like him better doing him as a 10th level fighter and 10th level mage EL 22 NPC. This way he has the spell threat of 1e and has the physical ability to "mix it up" with the party, like he did in 1e.
Besides, wouldn't a straight conversion of his vampire HD in 1e to a fighter level in 3e be a truer conversion anyway?
Plus, the recommended levels for 3e should be at least 11th. I am thinking 13th+ would be even be more reasonable. Especially since I have several adventuring parties running around inside, all vampires under Strahd's control. 3 of whom used to be paladins, not to mention all of the formal good clerics. Vampire rogues are pretty nasty as well. A monk hasn't been defeated in a formal adventure, yet. But I am thinking of adding it anyway, just because of the level draining nastiness.
The 3e group that got slaughtered (they attacked Strahd immediately, without looking for the icon or sunsword) had a gnome mage, elven Arcane Archer, a paladin, cleric, and a rogue. Only the Lawful Good priest was killed. The rest have joined Strahd's hoard. The priest is a Strahd zombie. Most of them were dominated and then converted to vampires.