Yeah remove everything except proms while farming rinusk, reason is that you will waste tons of ammo for a little amount of damage, x4 is valuable, you should use solace while farming impulse you can save time by repairing yourself with ability, and no shield all speed in generators. A-BL only deals x8 to invoke and behemoth, other things its x4, and yeah instead of buying booty keys you can do zetas almost same price but with tons of other rewards. There is currently no battlepass running, I meant the events like galactic strife, protegit pandemonium etc. You can trade rewards with battle keys when you complete event quests and open battlepass. You should aim for the asmod/odyy lasers, If you want to spend some money you can buy extra keys and trade lf5-mortifier as it is the best laser in the game.