This is my typical everyday "I'm playing [Octavia]" build. Easily my favorite frame in the game, this build has farmed just... so much stuff.

Mod breakdown:

[Corrosive Projection]: Armor is the only thing [Octavia] gives even half a passing thought to, this helps with that

[Cunning Drift]: I'd put in [Power Drift], but this build is already sacrificing more range than i'd like.

[Primed Continuity]: Duration is love; Duration is life

[Umbral Intensify]: Obviously you do NOT need to do this. use regular [Intensify] if you cannot put this on here. Seriously I cannot stress enough how unnecessary it is to umbral forma your [Octavia].

[Augur Message]: Duration is love; Duration is life

[Transient Fortitude]: The single best power strength giver in my opinion.

[Stretch]: Need range, especially with [Partitioned Mallet] in the build

[Constitution]: Duration is love; Duration is life

[Augur Reach]: even more range without dipping into the [Overextended] pool

[Partitioned Mallet]: The crown jewel of the build. This thing is insane. Good mallet and amp placement allows for more EFFECTIVE coverage of tiles, as line of sight is required for damage. Also frees you up to use resonator and still keep up a mallet on the ground. If you have not used this mod, I highly recommend giving it a shot

as for the arcanes, honestly [Guardian] is great, and energize to smoothen out your energy needs. I do suggest running energizing dash, but with careful ability use (no spam) you should be fine on your passive and the occasional orb.