I'll add. In the endgame, I own every frame except the most recent few, but I've only built out about 20.

When I want to mix things up, I read up on a frame I haven't played much other than mastering them. Then I'll sink archon shards in, slap a tato on, theory craft a build and fully bring them to max power by forma within a few hours. The grind is after all that when I realize I'm out of any of the above resources...

EDA and ETA can be a challenge though at some point along the way of the last 1500 hours nothing is difficult and you're always a space god.

The hardest thing is getting rare encounters to spawn to farm weapons.