You should know that Underrail is a combat game. Lots of combat (or use of stealth to avoid it). You do need to build around the idea of fighting, or you'll have a bad time. It's not all about fighting, but expect quite a bit of it (stealth can be an alternative to a lot of fights, but not to the point of neglecting combat abilities).
If you really want to minimize crafting as much as possible, don't play crossbows. Crossbows are largely about shooting "special" bolts and you really need to be able to craft these. Crafting special bolts is simple and straightforward (unlike some other crafting in UR), not very onerous, and probably not a big deal for most anyone who likes this kind of game . . . but if you have a particular aversion to crating, crossbows may not be for you. On the other hand, crossbows are fun to play, maybe you can get over this aversion w/ regard to special bolts.
You will want to look at the feats available and plan your character around feats. Most of your character build revolves around the feats you choose. Fenix is referring to the Marksman feat when he talks about the 5 DEX requirement. Yeah, you really want that on an xbows char. Likewise Special Tactics. Have you seen
http://underrail.info.tm/build/ ? I wouldn't try to plan out your full character in advance, but you can see what all the feats and feat requirements are there.
Psi is a good build if you don't like crafting. There is some cool craftable stuff for psi chars, but you can get by without it, at least as well as other builds.
I would take a lot less PER and more CON on a PSI char. Most of the secrets that are revealed with high PER are loot, and pretty ordinary loot at that. I can think of one "cool" exception, maybe there's a couple more, but I wouldn't bend my whole character around 1/2/3 things like this. You can see 99+% of the game with 3 PER. You probably will not see 99% of the game on your first playthrough anyway. It's a big world.
If not obvious, I wouldn't take Snooping either. Let that go and take something you'll use all the time (like Sprint) instead. You can play a high PER char another time and see those few things you missed.
You will have some issues with traps if you go low PER. There is a workaround for this if you decide you need it. Figure it out or ask for help.
You can get by with 3 CON, but I think you'll probably be happier if you go somewhat higher. Going to 6 CON opens up Fast Metabolism which is nice, especially if you have a psi character with a big psi bar (for example from the Meditation feat).
The only reason I'd take 7 AGL is if I wanted Interloper, otherwise 6 is enough. From what you've said, Interloper might be fun for you, it is a very noticeable boost to stealth (and stealth is extremely well done in Underrail). If you want to play a thief, well, with Interloper you can steal everything that isn't nailed down and sometimes pry up the nails as well.
(But note, if you make a psi character most of your feats should go toward improving your psi (Premeditation is essential), you can take Interloper but don't get too distracted at feat picking time.)
If you want to take Persuasion (not a bad idea given your interests), that goes well with a high WIL psi character. Don't get sucked into taking all 3 social skills though, that's too costly.
You get enough skill points to max out 8 skills. You can spread them around a little and support more than 8, but if you spread them too thin, you'll just be inadequate at lots of different things. You can probably support 10, 11, maybe 12 different skills. Not 15 or more, which I have seen people try to do. You should have at least one offensive skill that you max every level.
Good luck. There is a lot of story in Underrail, but you have to kind of pay attention and connect the lines/fill in the blanks for yourself. Usually there's not straight-up lore dumps like you get in other games. (However, just to tempt you onward, there is a big lore dump at almost the end of the game, filling in a huge amount of backstory, and it is just awesome, really well done.) Enjoy the game.