If you pick a base character then the prime gets removed as well, the better version cant exist without the base version, however if you remove a prime version then the base character can still exist. My personal pick would be Valkyr due to how [IMO] useless she seems
Oh yeah, infinite 0 drawback invisibility like Ivara, Ash, Loki, lol. Invisibility is useful, but make no mistake that it’s not invincibility which frames also have like Revenant, Valkyr, also Loki again, and other frames who have practical invincibility like Zephyr who can just float away from her only danger, melee enemies.
Now, obviously, other frames don’t have recastable invisibility but that’s QoL which proves my point. Enemies don’t detect you immediately the moment you leave invisibility, so you can chain it on any frame such that you’re never actually detected. It’s a matter of QoL preference, and most people prefer a single button press every X seconds (or once in the case of Ivara, lol) in contrast to Octavia’s crouch spam.
As for her scaling damage, it’s slow and relies on enemies targeting her mallet. A weapon will be faster at any level if you know how to mod it well, and any frame I’ve mentioned in this comment is completely capable of standing in one spot, though Valkyr would certainly prefer to run around and murder enemies.
The amount of button presses a frame requires is not indicative of their power level. I can kill everything in a mission with 2 button presses using Revenant’s 2 and 4 for most missions, maybe the occasional 3rd if I need Roar at higher levels. That doesn’t mean it’s quick, and that doesn’t mean it’s strong. I’m not saying Octavia is weak, but she’s not broken, at least not anymore so than the rest of the game (which I would agree is broken in general, lol).
Yeah Octavia is strong but she’s my last choice for a stealth frame lol. It’s clunky to use and her only good way to stay alive. I always go to Loki if I need stealth