5th level is a bit too early for it, but when fighting foes all from the same geographical area, Horizon Walker can get obscenely high favored enemy bonuses, since at level 3 in the class (9th level overall) you can choose a favored terrain and get that bonus as a FE bonus vs. any creature from that terrain. Since HW boosts favored terrain by +2 like 7 times over 10 levels and you can multiclass with rogue to enter and thus gain access to a rogue talent that also boosts favored terrain (and more importantly, then spam Extra Rogue Talent feats to improve it), and the boots of friendly terrain are another dirt cheap +2... by level 15 you can easily have a +30 bonus.
Some basic work I did on it long, long ago:
http://www.enworld.org/forum/showthread.php?310781-All-about-the-Horizon-Walker-%28Optimization%29Note that in a normal game, Guide Ranger is actually a terrible choice now. After I wrote that up, PF created the Instant Enemy spell. It's normally used to get your highest FE bonus against anyone, single-target. Straight forward and powerful. But...it's also useful to a Horizon Walker. Since they count as your FE for all purposes, that includes native terrain, creating a backdoor way for you to apply your ludicrous HW bonuses against anyone if set up right (being a level 3 ranger spell, you'd probably rely on a wand for this, and thus it's only worth it on bosses and TPK situations; but the point is you actually want to keep your FE class feature to utilize the spell).
But that's for a normal game with varied enemies and locales. If you're fighting in the same place the entire campaigh, HW is made for that shit. It's just...a bit too high level for where you are now. But keep it in mind should you level up and reroll PCs.
