I’m assuming you’re going for a semi-AA musket build. If that’s the case I’m going to recommend some alternatives.
Archer 3 QS 3 Musket example: http://www.tosbase.com/tools/skill-simulator/build/f8wcx2imub/
The above is a standard AA Musket build, give or take a few points. I moved a couple around from the standard to make leveling a little easier as well as give weapon swapping more potential. Also Stone Picking and Stone Throw are primarily PvP skills, but still have some PvE viability. You may not want to take them if you’re going for straight PvE DPS.
Now, assuming you went Scout for stealth and refuse to drop it, that’s understandable and fine, but if that’s the case, Scout 3 is pretty terrible. Here are a couple more alternatives for musket with scout:
Archer 2 QS 3 Scout 1 Musket: http://www.tosbase.com/tools/skill-simulator/build/ryf20e0od7/
I believe the above might be what you’re looking for, especially if you want a stealth musket build for PvP.
Archer 3 Scout 1 Rogue 2 Musket: http://www.tosbase.com/tools/skill-simulator/build/z1w31t02e7/
The above is actually a highly versatile and potentially amazing PvP build, I’d argue it has the highest versatility of any available archer PvP build, however it would rely heavily on situational play and weapon swapping. Your backstab won’t hit as hard as a C3 rogues and your musket won’t be as strong as an Archer 3 QS 3 Musket build, but they would only be 5-15% weaker and again, you would be able to play extremely well in 1v1, 2v2, 5v5, and GvG with this build as it is highly versatile, if you want one character that can do several things in PvP, this might be the build for you.
Disclaimer: If you think that you are not the best gamer, or are too casual to farm the gear a build like this would require, I’d stay away from it, since it’s likely a very difficult build to play well, seeings as it’s two completely different playstyles wrapped into one build.
Archer 2 Ranger 3 Scout 1 Musket: http://www.tosbase.com/tools/skill-simulator/build/8dnbem60r8/
The above is a pretty decent PvPvE spec; Archer 2 gives you decent buffs and your ability to weapon swap, Ranger 3 will be most of your AoE damage as well as a 20% damage boost to your musket skills for some serious burst dps in both PvP and PvE, and of course, Scout, 'cause Stealth.
I hope one of the above listed specs is useful or what you’re looking for.
As for stats, a lot of it is theoretical and preferencial, HOWEVER, if you’re looking for burst dps, which is what musket is all about, you’re going to want an insanely high strength build, due to the ~70% str boost you get at rank 7, and the % damage scaling on musket abilities.
If you’re going for a PvP build, you’re going to need a fair amount of con, especially if you decide to go with the rogue build as you’ll be weaving in and out of melee range.
In short I would recommend something along the lines of:
100-200 strength
50-150 con
0 int
0-40 spr
20-60 dex
Strength is such a powerful stat in general and with the bonuses you get to it, it’s hard not to stack it almost entirely.
The reason for the low dex is because in PvP, crit rating is unreliable, and in PvE it’s easy to get through gems. Max level crit rating gems give you an insane amount of crit without investing any dex. I only recommend 20-60 dex due as a blanket amount of accuracy and crit while leveling.
Intellect is useless, obviously.
Spirit is weird. It’s not exactly worth investing points into for PvP or PvE, however, you seem to be going for an ability-oriented musket build, in which case, you are likely going to want SOME max SP and SP regeneration, the block penetration is a bonus, and the magic defense is near negligible but still a small bonus. Hence recommending upwards of about 40 points in it, but anywhere from 0-40 is fine.
Constitution is sort of an “as needed” stat, however if you intend to PvP at all, health is always needed, not to mention, dying in PvE can get costly. 50 is enough to survive relatively well in PvE if you’re good at dodging mechanics and kiting. If you plan to be doing your fair share of PvP I would likely recommend 100+ con. Again, this stat necessity is pretty much going to change player-to-player, but health is the best defensive stat, so the more you can get, the better.
Again, hope this helped man, hope I didn’t go too crazy on the advice. 