I’m half-way through Sedna right now. I have just 1 Warframe (though I did start building Limbo last night when I remembered I did that quest) and it, a long with my best weapons, are maxed out and either at mod capacity or damn near (still need endo for a few). MR5.
I have a railjack, I unlocked the Operator, and I have so many resources and credits. But everything is starting to take forever to kill and hurts me so much. When I did the whole Drifter quest thing, I choose everything I already used but it was so much stronger. The Warframe had way more shield and health even though I have Redirection and Vitality maxed out on it. The Boltor had a super high ROF compared to what mine has and did way more damage.
How the hell do I get that kind of power on my normal stuff? I know about Forma but I haven’t even seen some of the mods for the weapons I have I’ve seen suggested for maximum damage, so I’m just hanging onto those until it makes sense to use them. Is that really the only way to get stronger?
Forma is extremely important. If you’re not using any that is probably your problem, you’re not modding properly. Sedna is where that’s going start showing. If you post your builds we could poke at them and let you know for sure but right now we don’t have much to go on. You can also look up build guides for the gear you like to use and try to get as close to them as possible. The element you choose for each faction can also be playing a role.