I suggest adding another semi-cursed item, one with drawbacks and benefits.

Ring of Anchoring
Prevents the PC from teleporting under any circumstances.
Autocursing.
About as common as wedding rings.

The obvious drawback, of course, is that you can't teleport--and it's autocursing, so you might put it on and then not be able to get it off.

The obvious benefit is that you can put it on, read your books, and not worry about blipping all over the place thanks to teleportitis.

It would also be an alternate solution for teleportitis, so that Lawful characters and aspiring platinum girdle owners would be able to deal with the problem of random teleportation (but also remove its benefits) without slaughtering blink dogs.

It would stop the PC from being teleported into the Arena, as well. The Arena Master should be aware of this, and tell the PC to take off the ring so he can teleport them to the fight. And it would stop fairy dragons and teleport traps from working on the PC.

It would remove an annoyance, stop people from needing to travel to no-teleport zones to read books, and offer some extra options for strategy, without being too powerful.