Paladins create a protection vs. evil within in a 10' radius. Personally, I have always thought this should have been a 10' diameter, not a 10' radius, as a 10' radius equates to a 20' diameter, which is a pretty damned large area. It does only give a -1 penalty to enemies' attack rolls, but to me a 20' radius (always active) is a bit much. A 20' diameter covers virtually the entire party in any normal melee situation. A 10' diameter would be more reasonable, covering just the paladin and anyone very near him. I'm hesitant to reduce this in my games, but I am starting to strongly favor the idea that it should be a 10' diameter, not a 10' radius.
The holy avenger sword has always troubled me, for several reasons. The details under the paladin class description conflict with the details under the item description. Under the class description, it says the sword dispels hostile magic (at the paladin's level) within a 30' diameter, which is fucking huge! And yet under the item description it says the sword only dispels magic in a 5' radius, i.e. a 10' diameter, which to me is much more sensible.
I have always ruled that the paladin must present his sword (unsheathed) and concentrate for the round in order to dispel the magic he wishes to dispel, otherwise (if the dispel is automatic by default even while engaging in combat), that to me seems too potent. When it comes to the 50% magic resistance in a 5' radius, I am tossed up on how I see that. On one hand, I like the idea that the sword is so holy and potent that it prevents magic from affecting the paladin 50% of the time simply by being wielded. On the other hand, that does seem pretty potent and I can see requiring the paladin to actively concentrate for the round in nothing other than resisting the magical effect he wishes to resist. I could go either way. Someone help me make up my mind!
It opens so many interesting possibilities!