Named Bullet, Stunning Critical, and Dastardly Finish

I'm trying to find a way to get both Named Bullet, Stunning Critical, and Dastardly Finish, all on the same character (preferably a Cha-based caster). The general character concept is to use the Starknife Divine Fighting Technique, cast Named Bullet to guarantee a critical on a ranged attack, using the stun to set up a coup de grace. Unfortunately, the prerequisites for each are fairly deep - requiring 5d6 sneak attack, level 4 spells, and 17 BAB.

So far, I'm thinking of taking the following route:
Rogue 3
Brawler 2 (Snakebite Striker)
Magus 3 (Eldritch Scion, for Cha-based casting)
Arcane Trickster 2
Eldritch Knight 10

A perk of the EK 10 is that it keeps both BAB and casting up, as well as helping with some of the necessary feats. Plus, landing a Named Bullet would trigger the Spell Critical to get another Named Bullet for use the next round.

The sneak attack die would be coming from the Accomplished Sneak Attacker feat. But I'm not sure it works without taking advantage of retraining to move a feat into Stunning Critical.

Alternatively, I'm thinking of focusing on Paladin, using Unsanctioned Knowledge for the Named Bullet. But that may run into trouble with the Code of Conduct (can Paladins sneak attack?)

Any help revising this would be appreciated.

The PF paladin's code requires acting with honor which prevents lying, cheating, poison use 'and so forth'. IMO there are still circumstances where you can use sneak attack but it'd be a pain, and there's room for more restrictive interpretations than mine.

As far as getting stunning critical without retraining goes you could be a half-elf and cast paragon surge.

BTW are you starting play at 20th level? A setup which doesn't work for 19 levels is a poor idea I think if not.

I don't really like paladin codes. Too restrictive and arbitrary- no using poison? I can slice a gaping, bleeding hole in my attacker's side but I can't weaken him with poison? Makes no sense. I go as far as allowing NG and CG paladins in my game, simply because I don't get why some good gods can't give their followers the ability to smite evil or get CHA to saves, and some can. A chaotic character can follow a code (their own or their deity's) and have strong morals. That's what I see a paladin as doing... not sticking to some weird set of rules from the middle ages.

Sneak attack is no more dishonorable in my mind than smiting evil or using a magic weapon- you're doing your best to kill evil things, it's just happening from behind (wink) and involves more precise penetration (wink).

I love Paladins, and I don't see their codes as a bad thing.
But ...
I also see nothing that says a Paladin can't sneak attack.
If I interpretted that differently (or played with a GM who did) then I would change my stance.
The number one rule for playing a Paladin is to ask the GM what their stance on Paladin codes is, because that'll determine how fun it is to play.

avrs question about starting level is a good question. What level are you playing at?

You can do 4th level spells and 5d6 sneak easy enough. But 17 BAB is just outright stating this wont ever happen.

It would be better to go unchained rogue and skill unlock intimidate and make them cower. That could happen a lot sooner at level 15.

Or you could look into getting a pet ankylosaur build, like hunter or summoning them and then do it that way.

There is a prestige class that, while it doesn't have to be a paladin to get in, is kind of built for Paladins of Ragathiel. The Crimson Templar PrC gets sneak attack and you have to worship this LG deity.

So yeah, I do think Paladins can sneak attack, especially if you worship any of the 'avenging' deities like Ragathiel.

The PF paladin's code requires acting with honor which prevents lying, cheating, poison use 'and so forth'. IMO there are still circumstances where you can use sneak attack but it'd be a pain, and there's room for more restrictive interpretations than mine.

As far as getting stunning critical without retraining goes you could be a half-elf and cast paragon surge.

BTW are you starting play at 20th level? A setup which doesn't work for 19 levels is a poor idea I think if not.

There's nothing in the paladin code that prohibits using the sneak attack class feature itself. There's some room for debate on particular situations for setting up sneak attack, such as the traditional "creep behind and backstab" situation, but there are plenty of ways to get sneak attack besides that.

This seems like a lot of work for one gimmick, though.

I think this idea would work a whole lot better for two characters working together.

One does a ranged stun with named bullet (or possibly doesn't even bother, with a 17 BaB you get plenty of chances for a crit without it) and stunning critical, the other does a coup de grace (which without something else has to be a melee attack anyway) with Dastardly Finish.

Unless this is a character that starts at high level though, it is still just going to be a very late game tactic.