Even 3 INT is enough if you eat Junkyard Surprise (with a bit of luck +2 INT) and 15% crafting bonus in Core City player home basement. Maxed 135 points at level 25 translate to as much as 167 effective skill and I don't rememeber ever needing more than 154-156, even for infused Leather armors so maxing it is overspent. When it comes to skill points take only more than 3 INT if you're playing a (hybrid) PSI build which usually needs to spread alot skillwise.
Crafting feats are not mandatory at all but they can make a difference between life and death in certain situations, especially on glass cannon builds that need to rely on shields and good armor resistance. It's always a matter if your build can actually afford 7 INT and has enough free feat slots.
If you're a pure sniper you qualify for both easily so take 7 INT for feats like Power Management and Skinner. You can even afford Gun Nut and still be able to max to 16 PER on level 24 which you really should do. High PER is more important then anything for a sniper.
Unless you plan to use a pistol or SMG as your secondary firearm drop DEX to 3. It's literally useless for a sniper. Those are whopping 5 extra points you can switch over to STR for efficient sniper use, INT for the crafting feats and AGI for stealth bonus and Blitz.
Start with:
5 STR, 3 DEX, 10 AGI, 3 CON, 10 PER, 3 WIL, 7 INT
Put every point into PER.
Alternatively you can take 3 points from AGI, put them into CON and pick Fast Metabolism which synergizes very well with Power Management and regenarative vest. Just remember not to to overspend on crafting skills - probably the most common mistake I've seen people do.