Not an expert or anything, but this is how I see the build being better:
Explanation:
A1 - Take Multishot 5, Swift step 5, 1 point into each of the remaining just for utility [save remaining points];
A2 - Take Multishot 10, SS 10, Kneeling Shot 5 and 1 point into Heavy Shot for utility [save remaining points];
A3 - Take Multishot 15 (Great dmg, specially paired with +AOE ratio gear), KS 10 (Great buff, specially on a high dex build), Twin Arrows 5 (Great single target dmg) and use the 2 leftover points where you wish (I put into SS just for better managing the 100% uptime);
R1 - Barrage 5 (Good AOE dmg), Steady Aim 5 (Dmg Buff), Critical Shot 4 (Best option over HA) and 1 point into High Anchoring to make use of its attributes and for utility of the skill;
F1 - Crossfire 5 (I believe this is why you went Fletcher in the first place), Broadhead 5 (Bleeding seems nice and its duration increases with skill lvl) and 1 point into Bodkin Point for it’s protective magic nullification (I don’t know if the defense reduction works on bosses, from what I saw the Full Draw defense reduction doesn’t apply so I am treating this as the same). I left Barbed Arrow behind because of its dependancy on enemy armor type, I don’t know how useful it can be on the right boss but I thought maxing the bleed would be worth more [save remaining points];
F2 - Magic Arrow 5 (Seems like a nice DOT), Crossfire 10, Broadhead 10 [save remaining points];
F3 - Magic Arrow 10, Crossfire 15, Divine Machine Arrow 5 and the remaining on Broadhead, leaving it at 14.
Feel free to voice your opinions, I didn’t play Fletcher yet so I might be wrong about its skills. For Archer and Ranger skills I am very confident on my choices though.