This was a character I had in 4th edition; the GM suggested I play a reboot of him for his Pathfinder campaign, and I like the character but I'm not sure if I can make him effective in Pathfinder. But I don't know Pathfinder as well; maybe someone can help me build it.
I need:
To be reasonably good at fighting with a shortbow, even though I won't have the points to raise my strength very high. (Ideally, I would also be able to do tricks like 4th ed.'s hunter ranger, like tripping with a ranged attack.)
A blink dog companion.
A rat familiar.
To be good at social skills. (He was sort of acting as an ambassador for the goblin kingdom.)
Some magic.
I could switch to a class other than ranger if it works out better, although ranger seems like a good base since it has an animal companion and spells (and the character was a ranger before.)
So, what I'm trying to figure out is, is it possible to be non-useless at archery even while spending most of my feats on other stuff like getting a familiar?
And would you go the Variant Multiclassing route to get a familiar, or Eldrich Heritage? (the character's mother was a witch who tried to teach him magic but he didn't really catch on. But he did get a familiar out of it. So I was thinking of doing variant multiclassing witch.)
Short answer is no.
You can be good at archery and the goblins +4 to Dex helps plenty.
Also no blink dog companion in pathfinder.
A goblin Ranger will never be good at social skills. You have a charisma penalty and I think intimidate is your only social class skill. However you could take the urban ranger archetype for additional social skills.
You can get a rat familiar for the price of 2 feats but you actually need those feats to be a competent archer.
Yeah that's what I figured. I could probably get the GM to make a new goblin race without the charisma penalty (since they're not Pathfinder goblins) but that doesn't solve the problem of needing all my feats to counteract ranged penalties.
I think you can get a blink dog with monstrous mount feat, or something.
To be reasonably good at fighting with a shortbow, even though I won't have the points to raise my strength very high.
That's easy enough fine; Goblins and Rangers both work fine for archery builds, and you only need 10 strength to avoid taking penalty. Just get your dexterity high and take archery feats, and you're golden. If you're not doing mounted combat, there's really no reason to use a shortbow over a longbow, but it's 1 point of damage on average so that's up to taste.
A blink dog companion.
I'm actually not aware of any way to get a Magical Beast as an animal companion, so you may need to rely on your GM making this possible. Monstrous Mount gives you a very short list of choices to pick from, of which Blink Dog isn't one of them.
A rat familiar.
You're best option is to multiclass into Fighter and take the Eldritch Guardian archetype. The other option is Eldritch Heritage, as you mention, but you're a bit tight on feats. Variant multi-classing is a bad idea here; if you want to spend feats to get a familiar, use Eldritch Heritage instead.
To be good at social skills. (He was sort of acting as an ambassador for the goblin kingdom.)
Kinda tricky with charisma being a dump stat, but if you just keep adding points to a skill you can be decent with anything.
Some magic.
Rangers get a little bit of magic in Pathfinder (more nature/druid themed than arcane themed, though) so that's already covered.
Yeah that's what I figured. I could probably get the GM to make a new goblin race without the charisma penalty (since they're not Pathfinder goblins) but that doesn't solve the problem of needing all my feats to counteract ranged penalties.
Your bigger issue is that no ranger class abilities are charisma-based, so you can't afford to invest many points into it. The -1 racial penalty just makes an already tricky situation worse.
If you're interested in a Goblin that doesn't sacrifice charisma, there is the Blue. It's 3rd party, but honestly if you're going to have one 3PP at your table Ultimate Psionics is it.
...Eldritch Guardian...
Oh cool, I was not aware of the Eldritch Guardian archetype. That does look like a good option.
Your bigger issue is that no ranger class abilities are charisma-based, so you can't afford to invest many points into it.
Yeah, the ideal thing really would be if there were some sort of ranger-ish class that did charisma-based arcane spells. Might there be a Bard archetype that would work?
(Probably not, I still need extra combat feats for my bow.)
Yeah, the Blue goblins look pretty good, I'll see about using those.
You could use the animal companion to simulate a rat familiar (you can pick dire rat). Then get leadership and ask to get a blink dog from leadership.
That could work! Except I want the rat to have familiar-level intelligence rather than rat-level, so I'd have to figure out a way around that.
My advice would be to take Eldritch Guardian 3/Ranger X. Use the EG's familair for the rat, drop all of your feats into archery but also take Boon Companion so you're effectively a druid of your Ranger level and take this feat from the Companions book: http://www.d20pfsrd.com/feats/general-feats/monstrous-companion
Why not go one level of witch to get the familiar? Helps with the "little bit of magic" part too. Background fits with his mother trying to teach him to be a witch, he picked up a little bit.
Nothing about this character is screaming ranger to me. I'd look at going fighter/archer or some other class with full bab. Cavalier maybe?