Ok so I know my build isn't optimized but it is what it is. What I need is some feat ideas for my character. I'm not really sure where to go with him at this point.
Class: Unchained Rogue 2/ Wizard 3 (divination foresight) / Arcane Trickster 1
Feats: Accomplished sneak attacker, Arcane Armor Training, Exotic weapon pro (Elven branch spear).
rogue Talents: Surprise attacks
I'll be lvl7 soon and I'm not sure what to take next. My role is scout, buff wizard and trap monkey. ATM I only do 2d6 sneak attack damage but at lvl7 I'll do 3d6. I usually get a surprise round on enemies and when they get one on me I still get to go and even if I loose initiative ( I have a +8 initiative atm) then surprise attacks talent lets me deal sneak attack damage anyways usually via acid splash cantrip. Anyways I'm rambling. Should I just go ray specialist with my feats? I'm also considering picking up craft wondrous items but we are doing a module and after book 2 or 3 pathfinder modules don't always give you much down time. Thanks in advance!
If you're looking for increased damage output I would look for feats that make your spells better.
there's also Bloatmage Initiate if you don't care about your character becoming disgustingly fat.
Crafting could be worthwhile if you think it will be difficult to acquire any/all of the following items
Right now you have a lot of dissonance in your build, and I'm concerned that your existing melee focus is going to become useless. You should seriously consider retraining to either better focus in your Elven Branched Spear fighting style, or to abandon it entirely.
I'm not sure why you even have Arcane Armor Training, as with 20 dexterity there is no type of armor that is actually affordable at your level that is better than the Mage Armor spell. At higher levels the Quicken Spell metamagic will come into play, and that's incompatible with Arcane Armor Training, so I don't really see you getting much use out of it. Better to retrain it in favor of a more useful feat.
As for Exotic Weapon Proficiency, the Arcane Trickster struggles due to his slow base attack bonus progression. Even making generous presumptions, it looks like you've only got +9 to hit. This gives you only a 55% chance to hit a typical CR 6 monster for 1d8 damage. Given that it's only one attack per round, no amount of buffs or Sneak Attack is going to make that salvageable, and this is only going to get worse at higher levels due to your slow progression falling further and further behind.
If you want to have a solid melee presence, there are two good paths to follow. The first is to use polymorph subschool spells such as Beast Shape in combat. This gives you a lot of attacks per round, compensating for your low accuracy with a larger number of chances to hit. However, this means there's no point in using weapons or armor whatsoever. The second approach is to retrain into the Eldritch Scoundrel archetype for (unchained) Rogue which supports the Elven Branched Spear fighting style much more effectively.
Finally, I'm not sure what exactly you're getting out of that second level of Rogue. Evasion is nice to have, but not worth delaying your spellcasting (just investing the extra slots you would have gotten in defensive spells will generally be better). Usually you either go for 3 levels of Unchained Rogue for finesse training (which, as mentioned earlier, works best with a polymorph approach applying the bonus to claw attacks) or stay with only 1 level of rogue.
In terms of how to develop as an Arcane Trickster, ray spells are indeed a good way to go. Without retraining, however, I don't think you have enough feats to really specialize in them. LordKailas lists a lot of the staple feats, but you absolutely need to have Spell Perfection by 15th level if you're going this route and just meeting its prerequisites will consume almost all of your feats and leave nothing for the other staples. Blasting spells are very feat-intensive if you want to be good at them. You may be better off just taking Precise Shot to shoot into melee and rely on sneak attack for damage (instead of feats to boost the spell damage directly). Crafting is always an excellent choice, although if you go down that path without investing in your arcane trickster abilities you may eventually feel like you may as well just be a single-class Wizard instead.
Don't take this too negatively; I personally love the Arcane Trickster, it's just a very unforgiving prestige class because its class features need lots of support to shine.
I don't consider 2 levels of rogue to be too unoptimised, I've played an arcane trickster identicle to this with one level of diviner and no exotic weapon prof. He has a very poor BAB, worse even than a pure wizard and no rogue tricks. The foresight diviner gets a fair number of pre-rolls which can make combat less risky. You could build a self-buff combat arcane trickster quite easily that also scouts/divines for the group. You are not optimised as you point out but you are playable.