I've posted about this setup a couple of times in comments in other build threads and people seemed interested enough that I figured I'd make a quick little guide for this setup, as it's treated me extremely well from league start all the way to clearing the atlas and all bosses.

The basic shell is aura scaling for giant armor and replica dreamfeather for big attack damage, while utilizing doryanis prototype to skip enemy resists.

I league started this as just a basic 2h trinity attack build, using this tree here: https://pobb.in/UlJyQZJa5b6A

It was able to clear in to red maps on basically self found gear with a 25c investment in to a 2h elemental sword. Entire campaign was run using smite+ancestral call+elemental damage with attacks+onslaught in whatever random 4link was available. If you find yourself lacking damage in campaign go to trade and set a level cap of your level, search for any 2h sword then sort by elemental DPS and buy the biggest one you can afford - there will be a plethora of random nonsense for sale for 1-5c in these level ranges. You can convert to crit once you're in maps to gain some more DPS over precise technique and buy yourself a fractured 2h sword with a T1 flat elemental roll of some kind (I recommend getting flat lightning here, so we don't have to use wrath early as the INT requirement can be annoying) and hit it with a few essences to easily get a ~1000 ele dps 2h that will work until you're ready for doryanis. Don't be afraid to use precision + arrogance to fix accuracy as you can easily fit in determination+grace and will be plenty tanky so losing the ~450 life for the precision reservation is very worth it.

The doryanis swap is a big overhaul so if you try this out don't try and piecemeal it - you need to stockpile all of the items and do it all at once or it'll feel really, really bad. Here's my current PoB for my character: https://pobb.in/DgiOn1poTjY2

Basically nothing checked in PoB, not even flasks, we have 4.5m pinnacle boss DPS, with a very respectable eHP pool (outside a couple specific mechanics like shaper beam which you should avoid standing in). This gets about as high as 9m DPS with flasks and other buffs up, and given the ability of smite to hit twice with proper positioning it clears pinnacles with ease.

I just map with awakened ancestral call in my main link in place of multistrike because I'm too lazy to roll +2 strikes on my gloves, and the larger singular hits without multistrike just oneshot entire screens anyway with all the smite overlaps. I only ever bother swapping back to multistrike if I'm doing actual pinnacles as it's total overkill for guardians etc and not worth the annoyance.

For sanctum specifically: smite has so much strike range and the individual hits are so large that it stunlocks guards (if they don't die immediately), and with ancestral call in the links it can hit every guard in the room with ease. I'm not really sure how or why this works as I had thought only phys danage could stun, but it definitely interrupts their attacks and they just stand there doing nothing. I haven't lost a sanctum run in 4-5 complete runs now. There's potential for the final-final boss to be scary in the lightning rings phase I would think given the doryani setup, but she always dies before she gets there so I can't say if it's really a problem or not.

A final note on gearing as it was extremely surprising to me: the doryanis conversion is super, super cheap. I guess everyone got their fill of it in kalandra or something? But a rough outline of what I spent to do the full conversion to doryanis:

Clusters:

2 large cluster jewel bases (use generic attack damage here, the dual wield one rolls too many weird notables): 10c each. Harvest reroll with an attack mod a few times to get 3 notables each - we don't need to be very picky here at all, as long as we can get life and mana leach someplace between both clusters.

4 small reservation clusters: 10-20c each. We don't need the big expensive ilvl 84 ones, any will do. Alt spam for introspection + literally any other rolls besides +lightning res.

Other gear:

Melding of the flesh: we want the "worst" resist penalty roll we can get here, and -4 max res. Mine cost 5c

Thread of hope (the "worst" roll you can find): 20c

Doryanis itself: 5c unlinked, 2divines linked. I'd recommend linking it given how cheap fusing are currently, and maybe spend a bit extra to get a good roll as it can have a pretty decent chunk of armor on it.

Alphas howl is 1c, can upgrade to a +2 corruption later on for a couple of divines, or try and make one yourself

Perseverance: 1c, you don't even really need this, but I found the permanent onslaught nice quality of life - note that it really only is giving you onslaught and some cold res, as we are 0 evasion so it provides none of the attack damage scaling

Replica dreamfeathers: 5c, though I would recommend splurging a bit here and get ones with a max attack speed roll, as we don't have a ton of attack speed elsewhere. Max attack speed rolls were 40-50c on last check.

Ventor's gamble: this surprised me perhaps the most at how cheap it was. The one in my PoB cost me 50c, but if you just set the rarity/quant to minimum 0 you can get one with the right resists and good life for 5c Gloves/boots/remaining ring are all just rares with fire/cold/chaos res and life, so spend as much as you like here.

There's still more upgrades I could make here I'm sure, but I tend to roll new builds before I get in to the absolute weeds of minmaxing things, and I haven't really felt the need to as I'm not really in the mood to try and do ubers on an attack build.