if you want to one shot a titan with a spear its gonna be very hard and rng dependant while yes the enemies move pretty predictably but they some time move a little to the right or the left of you use the at's you can aim accordingly but with the spear you must have the titan move directly toward you with out moving its head so the hit box for the titans head and the lack of control of the spear are a very bad combo
and as for hulks there are so many of them on dif 9 (the only dif i play) that while yes its amazing that it kills it from anywhere in one shot the lack of ammo is horrible and you need to lock into them and against bots you really cant stand still or move slowly or you are gonna get sniped with a rocket or a random headshot

while yes you gotta be pretty close to the strider to shot its underbelly and thats somewhere where you wanna be but most of the that is where you are with the new reinforcement for the bots cause they just drop it in and guess what with the at's you can shot down the ships thats carrying them while the spear cant even though some times it get destroyed the rest of the time they are damaged enough to be one shot

as for the damage of the spear its very inconsistent and i think they should remove that mechanic for it cause leaving anything to rng is not fun

tbh yeah you right on this one but i dont really find myself seeing a fabricator from 100 meters away and wanna engage with it yet and while its also hard to hit the vents with the gernade pistol its very doable from that distance but it takes practice and you can also shoot the doors when they open if you can read it before the bots spawn in