So I'm gathering comments to help our pal, Tom. Not to mention myself, and possibly others.
I'll be putting down my own thoughts and opinions on the matter as well.
Lets do the review.
The link to our topic at hand.
http://www.dorkistan.com/PFRPG/classes/ranger.htm
A quick cut of what it does.
The ranger can spend a day (8 hours) in training, study, or research refocusing a favored enemy slot. During this time, the ranger does not have access to the favored enemy slot he is refocusing. At the end of this refocusing day, the ranger must makes a Survival check. The DC of this check is 15 + (the favored enemy bonus of the slot the ranger is refocusing x 2) to confirm the refocusing. The ranger does not get his favored enemy bonus on this Survival check. If successful, the chosen favored enemy slot is refocused: the old favored enemy is lost, replaced by the new one. If the Survival check fails, the ranger retains the old favored enemy bonuses (which he once again has access to). If the ranger fails an attempt to refocus on a specific creature type, then attempts to refocus on that enemy again within one week, he gains a +5 circumstance bonus to Survival to confirm a refocusing. If the ranger attempts to refocus a favored enemy slot on a creature type he has had as a favored enemy before, he can do so with only a half-day of training, study, or research (4 hours).
New Favored Enemy Feats
The following feats expand the above favored enemy mechanic.Improved Refocus
Prerequisite 5th Level Ranger
Benefit You can refocus a favored enemy slot with 1 hour of study, training, or research. You can refocus a favored enemy slot on a creature type you had as a favored enemy before with 10 minutes of focused meditation.
Normal It takes 8 hours to refocus a favored enemy slot to a new creature, and 1 hour for a creature you've had as a favored enemy before.Versatile Focus
Prerequisite 5th Level Ranger
Benefit You permanently lose your favored enemy slot I (+2). In exchange, you can use a standard action to make a Survival check (DC 15 + creature's CR) to gain a +2 favored enemy bonus against a creature within 60 feet. The creature cannot be of a creature type that is currently one of your favored enemies. The bonus gained from this feat only applies to the specified creature, not a generic creature type. You gain this bonus for a number of minutes equal to your ranger level.
My opinion on it.
I like the idea of having a versatile focus, I also like the idea of being able to retrain bonuses.
I dislike the feat which makes you only have 1 hour to retrain. I see that as too much of a buff to the class feature.
I think that 8 hours may be too low an amount.
I am not sure about balance, so lets gather some opinions.
I'd say only allow one shot at it, and on;y when the character levels up. Just my instinctive reaction.