"Best" is personal opinion.
DPS:
The more hits U can land in a second, the higher your DPS will get. If you get +XX damage on those hits, your +XX damage will be more effective on something that its fast, rather than on something that hits slow.
Thus: (Wiki quote)
Daggers 1.33 seconds
Axe 1.33 seconds
Sword 1.33 seconds
Scythe 1.75 seconds
Hammer 1.75 seconds
Spear 1.5 seconds
Bow 2+ seconds
Daggers have the inherent ability to Dual Strike. Every time you Dual Strike, Spirit's Strenght will trigger twice, and thus be more effective than if you were to hit once.
This makes daggers the "best" choice if you're thinking purely about (ab-)using SS to it's max.
Axes/Swords are nice to have for some extra DPS comming from bleeding, DW and whatnot else. Also Distracting Blow, Strike, Chop, Bull's Strike, etc... are HIGHLY effective. (Bull's does BIG damage, regardless of not having strength, you'll hit 100+ easily)
Spears are nice, because spears are overpowered. Melee DPS is always messured on a target standing still. Thus the actual DPS for ANY melee weapon (Daggers, Hammer, sword, axe,...) does NOT reflect it's true DPS, as kiting can easily halve the number. With spears, however, kiting is harder (Strafing does occure, but not hardly as often as hits getting "kited" away).
Thus, even tough Spears seem a weaker choice, the actual DPS is about the same (if not higher) than melee options.
Bows are bad. It's that simply. Rangers, unless your name is pewpew, are not made for DPS, and thus adding a DPS skill to this, is pointless. Yes, you'll do a 50 damage distracting shot, and a 100+ damage sloths, but in overal, you're still not doing that much damage.
The only use I can see for /R, is either the overpowered interrupts (Savage and Dshot) and/or spike builds that have 3 of these spiking at the same time. (Bow's spike damage is redicilously high)
It's the same deal with Scythes. Average DPS is NOT that high, esp. not compared to daggers under SS, but the spike damage, once again, goes through the roof. Get 2 lucky crits, and you'll easily do 300+ damage.
Last but not least, my favorite:
/E:
Conjure flame the motherRED ENGINE GORED ENGINE GORED ENGINE GORED ENGINE GOa, and go totally imba using some Fire AoE.
[build prof=Ritualist/Elementalist][Spirit's Strength][Weapon of Aggression][Conjure Flame][Glyph of Lesser Energy][Meteor][Teinai's Heat][Searing Heat][Resurrection Signet][/build]
-68 DPS (about the same as warrior in Frenzy I think) wanding targets: CHECK
-Overpowered AoE (Searing, Tenai's): CHECK
-Armor ignoring damage: CHECK (SS)
-A whole lot of fun: CHECK
In the end, it's up to you. I pretty much mentioned everything these is to be mentioned, so it's up to you to decide what seems best/most fun
Bows are bad. It's that simply. Rangers, unless your name is pewpew, are not made for DPS, and thus adding a DPS skill to this, is pointless. Yes, you'll do a 50 damage distracting shot, and a 100+ damage sloths, but in overal, you're still not doing that much damage.
