PVE will A Higher Perc do more.
Spotter is 7% crit chance I believe, so theres that, so with fury thats +27%. ontop of whatever your gear gives you, that being said, there is alot to take in here. First is you cant crit world bosses/Structures, this is a pretty big deal.
http://gw2skills.net/editor/?fdAQFAEGBAAGFQjPDA-TRxEwAB3fgoyPT6Aqp+DAzPAA-e
this gear set up reaches 99% crit chance with spotter/fury and well over 100% with warrior banner. imo, thats a waste of potential because you are losing power when you are getting way to much crit chance.
http://gw2skills.net/editor/?fdAQFAEGBAAGFQjPDA-TRxEwAB3f4myvaq/oRHAAzPAA-e
this set up gives you EXACTLY 100% crit rate at all times with banner/fury/spotter.
with banner, you are doing 219% critical damage. so lets use bomb 1 as the baseline here. it does 902 in this build, (im talking untraited here.) you get +7% damage for having a pet. or 2113 crits no might stacks, no traits, no nothing for the baseline dps for this build. if we account for 25 might stacks, it is 3025 per hit no traits again.
lets compare it full zerker strength runes.(meta)
http://gw2skills.net/editor/?fdAQFAUE9ZNCAAMKgGfGA-TRRDgA9K/eV/hd/BQdAAmfAA-e
build has with fury and banner/spotter 81% crit chance at 212% crit damage, assuming they crit at 81% of the time all the time(n oreal way to test this other then to assume vaccum scenerios) its equal to an overall damage increase of 171%
1431 on base hit 25 might stacks, or an average of 2447 if it crits 81% of the time, and 7% damage from strength runes, 2618 average bomb damage.
id didnt account for minor in firearms which is 10% crit chance at sub50% enemy health, and from here you can mod all the number % wise for vuln etc. it might be wrong due to how certain damage mods stack etc. but it seems atleast at exoctic level a mix of Assassin and zerkers is the best.
However, at Ascended, if you use crit chance sigil for +7% crit chance, and you have banner + spotter + fury, you obtain 94% crit chance. which is pretty much enough, and going ascended assassins is pointless since you can already with the buffs go welllllll over 100% making it pointless to stack more of it.
Thats my general logic on the matter, take it with a grain of salt, I run full zerkers cause I do alot of TA, and the bosses there at the end dont get crit. :>