A week ago I tried traps crossbows in the early game on Hard and I can say that they're probably one of- if not the weakest build in the early game right now. I have roughly 1k hours in the game, most of it is on Hard but I also tried Sledgehammer right after and it was extremely easy early game (no shit sherlock moment ngl). Crossbows struggle really badly against early game mechanical damage threshold and have horrid damage-per-AP ratio before you get ap-cost reduction sources on the build in the mid-game (and also crit w/ crit damage, ect...). The extra durability enemies get makes it really easy for them to stall out your early game cc spam options and walk you down into melee range where you suck complete ass (kind of even incendiary grenade fear reliant).
A lot of other weapons don't really lose to mechanical threshold much at all (or at least have expose weakness if they do). Like, imagine firearm pistols which seem like they'd be bad against armor but don't need Strafe and get better rather than worse at melee(accuracy boost) with high ap-cost efficiency from early Dex value and the Gunslinger feat. And, heavier pistols are possible to just drop off enemies like a .44 out of nowhere (easy to make one too). Compared to crossbows, you would be likely to have a lower ap cost with a freaking sledgehammer with the common lifting belt loot and a 1-turn cd pummel, and you'll deal like 5x as much damage per hit after skipping mechanical threshold and the str damage bonus. (And also need like 10x less money to kill an enemy on average, and I'm not even exaggerating). Even a feat-less knife build will deal almost double the damage per round.
Expect 90% of your crossbow build damage early to come from bear traps, the rare burrower poison caltrop stack and all the incendiary grenades you can buy from Quinton in SGS. Like, the raw "value" of a single MK I Incendiary Bolt is 80% of an Incendiary GRENADE (and the attack is 25 AP instead of 15 AP, oh mama mia... you can fish for "Fear" but it's better later on). The blueprint also only makes 3 special bolts, better, but not really nearly as much (EARLY) power as an incendiary grenade honestly.
I think I would bite the bullet, and use level 1 Polymath and Aimed Shot, with attribute spread of roughly 3, 7, 6, 3, 10, 3, 8. You can use the massive overall skillpoints advantage to do a lot of throwing/crafting/trapping and subterfuge-stealth to cheat your bad early game a little. Stealth skip as much combat as you possibly can. You can also take Escape Artist painlessly if you want to, with the skillpoints and high dex/int. I'd take Strafe, Sprint at levels 2 and 4, in that order. You can instead go INT 9 instead of DEX 7 to take "Specialist" at level 16, losing 1 point of PER at level 16 (can boost with Juice, Salad, Marsh Honey for +4 PER still). It can make your late-game Critical Power really funny.
Also don't do a hybrid of melee/crossbows. It would be better to reload when you get surrounded or just go for a yolo tank crossbow troll build than to try both, sadly, and to be perfectly honest with you.
edit: oh yea and a large advantage of crossbows is that they are good against energy shields for a ranged weapon, and no enemies have energy shields in the early game.
