I'm currently playing an Investigator in a Pathfinder game and think I've already gone sub-optimal in my build, so I'm trying to rectify that. We have three front-line fighters (A Bloodrager, a Druid, and an Inquisitor), so I went with a ranged build, focusing on debuffing and archery. There are a few homebrew things going on in this campaign. First, Combat Expertise, Power Attack, and Deadly Aim are all gone as feats. They are simple combat options for anyone with a BAB of +1 of higher. Weapon Finesse is gone as a feat, anyone can simply replace Dex for attacks with "Finesse Weapons". A bunch of the "Improved" feats have been combined into "Powerful Maneuvers" and "Graceful Maneuvers", so there's no "Improved Bull Rush", "Improved Overrun", et cetera. Point Blank Shot is gone, Precise Shot stands in for it as the pre-requisite. Flurry and Greater Flurry are feats that anyone can take, which gives them more attacks per round similar to the Monk ability. Anyway, if you see anything that you don't understand, it's probably homebrew. All Pathfinder books are allowed, but no 3.5 stuff unless I can convince him. Here's the build so far:
Gold Elf
S12 D17 C10 I20 W15 Ch7
Character Options - Bonded Questioner (Bardic Magic in place of Alchemy, Familiar instead of Poison Use)
1 Investigator +0 Improved Initiative
2 Investigator +1
3 Investigator +2 Graceful Combat (Elven Weapons) Comabt Trick: Weapon Group Focus (Elven Weapons) (Retrain)
4 Investigator +3 +1 Int
5 Investigator +3 Precise Shot Quick Study
6 Investigator +4
7 Investigator +5 Ranged Study Sickening Offense
8 Investigator +6/1 +1 Dex
9 Arcane Archer +7/2 Flurry
10 Arcane Archer +8/3
11 Arcane Archer +9/4 Clustered Shots
12 Arcane Archer +10/5 +1 Int
13 Arcane Archer +11/6/1 Greater Flurry
14 Arcane Archer +12/7/2
15 Arcane Archer +13/8/3 Rapid Shot
16 Arcane Archer +14/9/4 +1 Int
17 Investigator +14/9/4 Improved Precise Shot Combat Trick: Weapon Group Specialization (Elven Weapons)
18 Investigator +15/10/5
19 Investigator +16/11/6/1 Arcane Strike Greater Combat Inspiration
20 Investigator +17/12/7/2