I know there are a lot of these, but here's what I'm looking for: sniper/psi with accessibility. That is, lockpick hack ect. Also open to psi/assault weapons or smg/psi.
All of those are perfectly viable.
I hate getting locked out of areas/options in any RPG, so I want high hacking/lockpicking/persuasion, never really use pickpocket.
Hacking/lockpicking are enough to see pretty much all the content there is to see in one playthrough (except for a few areas that are mutually exclusive to each other, depending on which faction you join later in the game).
Pickpocketing is handy, especially to get money and resources early on when they are still an issue. Also can be used to steal things like keycards or important quest items, but it's overall less usefull than hacking/lockpicking.
Persuasion allow you to resolve some quest in optimal ways, but it's not necessary to see all the content the game has to offer. Same with intimidation, but it's a little less useful (can be used in combat with the Yell feat though).
I'm new to this game, should I only specialize one weapon type, are the above combos viable?
You could probably make a working build that uses literally all weapon types and still make it viable, so no, you odn't need to specialize in only one of them. You can, and it will save you some skill points and a lot of feats, but you don't have to. Keep in mind all guns share the same skill so it's quite ergonomic to pair the sniper rifle with pistols, SMGs or ARs.
which crafting specialties?
No matter what your build is, you can always benefit from all crafting skills in some way.
That said, in my opinion, sniper builds really should have high mechanics and some electronics to craft their own sniper rifles. Other builds can kinda get away with no crafting at all by using unique weapons and those found in shops, but sniper rifles benefit from crafting their own rifles soooo much you really want mechanics to be high.
Another crafting skill is electronics- you will need at least 25 to use anatomically-aware scopes for your sniper rifles, but beyond that it's up to you. Good electronics skill means good energy shields, good night vision googles (which are very important for snipers, but can be bought in shops) or other gadgets like tasers and smart modules for guns.
Chemistry is in my opinion the least useful of crafting skills, but it has its uses as well. On sniper builds I usually put at least 35 points into it to craft special 9mm bullets for my sidearm, but you can skip it if you want.
Biology is extremly useful, but not necessary. It allows you to craft a number of really powerful drugs that can easily turn the tide in many fights. With 80 biology, you can make a pill that makes you immune to all CC effects like stun/incapacitation and that's really the main selling point of biology if you ask me.
Tailoring is also up to you. You can craft powerful armors with lots of different bonuses with it, but it's not really necessary and you can do just fine with armors you find or buy.
So to sum it all up, definitely take mechanics, take at least 25 electronics and the rest is up to you, I recommend all of them.
which psi abilities?
This depends. I don't play psi builds all that often, but if you only care about CC, I would put 30 points into Psychokinesis skill and take telekinteic punch/electrokinesis to stun your enemies. You can also put 30 points into thought control and take fear, but I find stuns to be more reliable. Remember to not spread yourself too thin and that taking the psi pill reduces your overall health by 25%.
Ideally give me the initial values (strength ect) then tell me the skill areas to emphasize and I'll go from there.
I can post how I usually play my snipers builds, but they are a tiny bit different than your idea (no psi, pistol instead of SMG as a secondary weapon). As a general rule, loko at the feats, choose the ones you like, and distribute your ability points so you can take them. Then put the rest of your points into perception.
5 STR- no much to talk about here, you need 5 STR to use pretty much all sniper rifles (6 for one unique model) so that's exactly how much yo want.
7 DEX- for Gunlinger (pistol feat) and sometimes Escape Artist feats. SMGs are going to benefit from high DEX, but you don't need 7 since none of the SMG feats require that much. Escape Artist is handy forany build though.
6 AGI- for Sprint feat. You can take 7 for Interloper if you like to sneak around, but I sneak around a lot and find that it's not really worth it all that much. It's up to you.
5 CON- simply to survive. I often play perma-death so I don't like glasscannnos with 3 CON, but it's also up to you.
8 PER- as much as you can get, at least 10 by the end of the game for feats like Snipe and Sharpshooter.
3 WILL-I don't play with psi so I have no use for Will. You don't really need to put any in it if you want psi for CC only though.
6 INT- I raise this to 7 later for disassemble feat, but this is purely for convenience. Go with 7 if you want to use crafting feats, 6 if the crafting feat you like happens to require that much, or 5 if you odn't care about the feats.
As for skills:
Guns- max them every level, self-explanatory.
Throwing- very useful, I would start with 10 and put some odd points from time to time until you hit 80-100 efffective skill.
Dodge/Evasion- I'm not a fan of those skills to be honest. You need to invest a lot of points into them to make them useful and I often can't find that many points to spare. I would skip them, but if you do want them then know that it's "do it right or don't do it at all" kind of deal. If you can't reach 200+ effective skill by the end of the game, it's a waste.
Stealth- max it. Your Snipe damage and maybe Ambush critical chance will depend on this, so you want it as high as possible. And stealth is just really useful in general.
Hackin/lockipcking- you can max it every level, but you don't need to. With 7 DEX, I usually put 10 points at the start of the game and try to rasie the effective skill by 5-10 every level. This is enough to open pretty much everything at any point in the game. Once you reach 120 effective skill, don't put any more points.
Pickpocketing- up to you.
Traps- I would get atleast 40 points to set crawler poison traps. Very useful and cheap on skill points.
I already talked about crafting.
As to psi, get those 30 points in thought control/psychokinesis if you care about CC only.
Max persuasion every level.
Aimed Shot, Sharpshooter, Snipe and Critical Power are essential feats for snipers. Spec Ops, Commando and Kneecap Shot are eesential for SMGs. You don't need any psi feats if it's CC only. If you want to play with pistols like I did, Gunslinger, Kneecap Shot, Rapid Fire, Point Shot and Paranoia are all good choices.
Why pistols? Because they are reliable, have good damage, no penalties, precision bonuses, and with Gunslinger they get a sweet +7 initative. Pair that with +5 from Paranoia and you have pretty good chance of winning Initative when your stealth approach fails or when it's not possible (like Arena for example).