PF Investigator Race?

[Uhtred]

One of my players is looking at the Advanced Class Guide Investigator hybrid class, and all I have heard is good things about it. The class would fill a couple of party holes (utility buff/skills) so I've elected to allow it. He's very excited. So apart from the standard Human (with +2 to ability allotted to Int) what fits as an optimal Investigator race? All PF materials allowed, no 3.5.
I've come to respect the Undine, whose +2 to Wis and Dex would serve him well, with a couple handy abilities to boot. Is there a hard-and-fast "Of COURSE you should be this" race for him? Something that boosts both Int and Dex?

[Khosan]

Tiefling's a pretty decent choice. +Dex/Int, -Cha, bunch of handy miscellaneous stuff.

There's also Ratfolk. They don't have as many handy things, but I love them all the same.

[Serafina]

Half-Elf is hands down THE best race for an Investigator.
Why?
Because of their favored class bonus - they can add 1/4 per level to the result of their Investigation-dice. Not only can this significantly boost their skills, but it can also increase their combat-ability (it can boost Initiative-checks, attack rolls and saves (with combat inspiration and/or a lepistadt investigators hat) and even damage (with combat inspiration and an inspired weapon).

Their +2 to stats is also good.
Skill Focus is not bad either, but can also provide a good weapon proficiency instead (this bars using inspired weapons, but can be worth it.
Drow Magic is a good alternate racial trait too, since it can open up Arcane Strike. The same goes for Mordant Envoy.

Elves are also pretty decent - instead of increasing the quality of Inspiration, they can increase the quantity. +2 Dexterity/Intelligence is also good for a ranged/finesse Investigator. Note that the FCB-option can also be grabbed by Half-Elves.

Other than that, well. The other favorite class bonuses are pretty bad (adding an extract to your formula book only saves some gold, a small bonus to perception and trap sense while underground is hardly good either and while adding to critical confirmation is nice, it doesn't stack with other sources).
Any Race that gets no penalty to Intelligence can make a decent Investigator. Getting a Bonus makes it better, and so does one to Strength or Dexterity. That gives you a lot of options, but Elves/Half-Elves/Humans are really your best bet.


An Investigator can basically select three combat styles: Brute, Finesse, Ranged.
Brute just uses Strength and has the advantage of taking the least feats for combat, so ironically they make the best skill-monkeys.
Finesse needs at least Weapon Finesse and a way to add Dexterity to damage, so thats two feats down (or one with an Agile weapon).
Ranged is the most feat-intensive, but compensates for the Investigators relative squishiness. You need Weapon Focus, Ranged Study (http://www.d20pfsrd.com/feats/general-feats/ranged-study) and all the other feats that are needed to be a good archer. Note that the range restriction of Ranged Study ONLY applies to Studied Strike - you get the benefits of Studied Combat regardless of range. Sadly its a huge feat tax so being human or dipping a few fighter levels may be necessary.

[Psyren]

Aside from the stat bonuses and the regular race perks (e.g. a human's bonus feat), another good thing to look out for are the favored class bonuses. Your ideal race will be generally strong, have favorable stat bonuses (Dex, Int or both), and have a good FC perk as well.

Humans are ideal because they hit all of these notes - bonus feat, great FC bonus (free formulae), relevant stat (Dex or Int) as well as other general human perks like Racial Emulation. There is also a minor flavor aspect because humans have a reputation for being inquisitive.

Elves and Half-Elves are also useful (hit many of the notes above and get inspiration boost FCs), Gnomes (Dex boost and free formulae.) Half-Elves have the additional benefit of having a mystery to solve built right in from the start, i.e. their parentage, and that gives the DM all kinds of plot hooks for them to suss out.

Ratfolk and Tieflings are good choices as well, though I prefer true Alchemists and Magi for these.