I'm a GM running LoF with a player who took the Finding Haleen feat. For the record, the way I converted the trait to Pathfinder was to say that whenever the PC takes a level in the class Haleen encouraged, they get the +1 hit point and +1 skill rank favored class bonuses rather than either/or.
My take: As a trait, looking purely at the mechanics, it's overpowered. Virtually identical to the Fast Learner feat, in fact, save that Fast Learner can apply to multiple favored classes, should the PC have more than one. (On the other hand, Finding Haleen doesn't include Fast Learner's human prerequisite.)
But that said, Haleen holds the potential of being a lot of fun in-game. In my campaign, she's become a PC's cohort--but not the same PC who took the trait--and I might, depending on how the timing works out, try adapting Broken Chains to resolve her "bad debts in Katapesh" backstory. Sure, a PC who takes Finding Haleen is basically getting a half-feat boost over everyone else, but for me that's definitely worth it to fully integrate Haleen into the story.
If you want to take a roleplaying stab at balancing Finding Haleen vs. Fast Learner, I'd offer this off the top of my head: The PC only receives the benefit of the trait so long as Haleen is alive. If something terrible befalls her, the PC's sorrow means they no longer receive the extra favored class benefits from there on out (though they keep whatever they already earned).
I took finding Haleen as a trait. I played a monk/rogue.
The DM flubbed the whole thing when we met Haleen he didnt describe her in a way that I recognized her, she was a beat in battle with her combat expertise, then entire party wasted everything that had trying to defeat her and I eventually had to grapple her and the rest of the party stuck her like a pig.
When everything was mopped up for the first mod, I was like whatever happened to this Haleen chick? The DM was like "oh yea that was her".....Doh.
I'm getting ready to run Legacy of Fire pretty soon once my Carrion Crown campaign wraps up, so I've been trying to find ways to alter the trait into something less powerful. As it is, it's way more beneficial than any other trait.
I was thinking of changing it to something like the original Heirloom Weapon, which still kind of keeps the flavor of the trait in my mind.
well i dunno. The preferred class bonus is +1 skills or +1 hp. That's normal, this trait let's you have both. IT might be worded badly, but as I read it, it's intent is to give you the OTHER preferred class bonus you don't choose. If you choose +1 hp, it gives you +1 skills and vice versa.
So effectively adding this trait to already existing rules makes it look more powerful than it is. but I dont think it's intention is to STACK with perferred class bonus. and of course if you take another preferred class bonus, that are now available and weren't when this was written, you as GM could either say, your not eligible for this trait, or It gives you a +1 or +1 your choice.