I have this build lying around for my next playthrough:
https://underrail.info/build/?HgMHBQMQAwkAAMKgAAAAwqBMSWBiUWooT2AAAABGNwBRASYiYTA1K8KHwohMasKASzPChcK1azjio7EF4qe-Ct-_I'm optimizing for oddity so I'm really trying to avoid combat as much as possible. That being said, when faced with violence the best plan for this build is using crowd control to tell them to hold their horses and getting extra damage from doing so (and also, some oddities are only obtained by killing critters/robots).
Base Abilities:DEX 7 for quick tinkering
AGI 5 for Quick Tinkering
PER Max.
INT 7 for Bowyer
I put the two remaining points in INT as well to boost related skills. If you don't want to play oddity, you could put those 2 ability points in CON, AGI, or maybe WIL, and take the missing skill points from persuasion and pickpocketing, the latter being more important.
Feats:Opportunist, Sure Step, Deadly Snares, and Quick Tinkering all go together really well. The idea is to get the most out of bear traps, acid blob traps, EMP mines, caltrops, and many other stuns/slows. Marksman and Special Tactics help with special bolts; Bowyer, Critical Power, and Sharpshooter help with crit damage (from Aimed Shot and Deadly Snares). Elemental Bolts because more damage is always good (and, in harder difficulties, non-negotiable).
I threw in Snipe and Blindsiding because they're always useful and powerful.
Psycho-temporal Acceleration and Future Orientation allows you to cast psycho-temporal contraction again as soon as it runs out (by spamming limited temporal increment) with the added benefit of perpetually reducing cooldowns and buffing psycho-temporal dilation (the one that slows).
I threw in Concussive Shots because I didn't really know what else to put and more slows are always welcome. Kneecap shot is a valid alternative. Having multiple sources of slow is amazing because you can get many high-priority targets or just stack everything on one dude and ruin his day like that.
Left out ambush because traps kind of made it redundant, both in terms of crits and evasion. I would've like to put in Strafe but I feel like you to keep your character in focus anyway for sharpshooter.
Optionally, you could drop Bowyer, Blindsiding and maybe Conscussive Shots/Sharpshooter in favor of Versatility, Cooked Shot and maybe Mad Chemist In order to use an Acid Pistol. But that would require dropping the low AP crossbow, and putting 35 points in guns. I never really used Chem Pistols so isk how it would play out.
Skills:Maxed crossbow. No throwing because traps and bolts fill a similar role.
Enough stealth, hacking, lockpicking and pickpocketing to get everywhere and everything.
Crafting has enough points to make anything this character could ever need (albeit sometimes needing the crafting table buff and hypercerebrix - but realistically it's not feasible to get materials with such high quality that you would need those).
70 TM to get that combo I mentioned before, use every TM ability.
Enough mercantile to get every merchant's hidden stash and enough persuasion to avoid most instances of combat where that is an option.
A few select hacking and mercantile skill checks will need a hypercerebrix as well. Couldn't budget enough skill points to make tier V explosives in any capacity, but with mines that just means placing more of them to make a bigger chain reaction.
Gear:-Night Vision Goggles (preferably adaptative, I think smart could help with Snipe damage but that's very circumstantial)
-Tactical Vest/Leather Armor
-Bolt Quiver
-Tabi for stealth
-Jawbone - before rathound king a Zephyr with super string and anatomically aware scope would be ideal.
-Cyclone with pneumatic reloader and anatomically aware scope.
-Jackknife in inventory
-Any electrical device you can think of.
-Hacking/Lockpicking tools.