I've been playing this RF Jugg for a while now (playing PoE for the first time). Kind of hitting a wall right now. I've seen on pohx FAQ that a good DPS threshold is 600k for RF and 2.5m for fire trap (for starters anyway).

Right now I'm at 354k for RF and 725k for Fire Trap and I don't know what else I should improve? I'm also having a hard time farming currency (most are indicated in Delirium on the atlas and I've grown and sold cold POE orbs, POE Currency) so any advice in that respect would be good too. Just a note about gem levels - I accidentally (sort of) decided to upgrade my main RF gem from level 20 to level 1 at 20% quality, so I'm upgrading this gem in my traded gear and the main gem is still leveling up (currently at level 18) so I know my DPS for RF will increase a bit more once it hits level 20. Hoping to transfer 20% quality mine to vaal RF 21/20 and sell for god 11 but yes I have about 1.3 currency divs now.

So I didn't play RF Juggernaut until late game. But I played RF Inquisitor.

A few things to consider in terms of upgrades. Helmet: pretty decent. I guess that's where your Firetrap plugs in. But you can make or buy a better one with focus effect, elemental damage, burn damage. If you get a good bar, some players swap their RF into the stick and throw a Firetrap 6L, to help with single-target DPS.

Armor: Basic/ES running armor is pretty wasteful for Juggernaut (great for Inquisitors). Upgrading to pure armor or brass dome will greatly increase your armor via Juggernaut's ancestor button and with Brass Dome you will get maximum resistance and reduced critical hit.

Boots: Very good.

Gloves: They're okay, but you don't need to stimulate overgrowth. Instead, you want multiple implied firing points. Of course you can get better/higher results for regenerating life, resistance, life, etc... Scepter: big improvements to +1 fire and +1 magic with damage over time, multi-dot, etc.

Amulet: Similar to Scepter.

Shield: Swapping for something like an Aegis or a rare Shield with max stamina can get you Melding of the Flesh, which can get you 90 stamina of all eles, making you super. cattle.

Rings: They are quite similar. You can get higher level resistors, catalyze them, etc. I like to be flexible with my rings because I use them to strengthen my attributes and resist demands.

Belt: You have a rather weak Immortal Flesh. Literally you can get 100 extra lives regenerated from a better one. In addition, you can choose Stygian Vise with % of max health, health, Heal, rest. Which is better since you can use an additional Abyssal gem to gain immunity to damaged health, resistance, damage, etc. This means you will have an extra passive point.

If you drop some fire clusters at the top and save points here and there, you can swap out a large passive cluster of 8 with elemental or fire damage giving you another 2 gem niches.

Jewelry: Ability to seek Meat Merge Exchange. Unbelievable. Not 100% necessary, but very good. The eyes of the observers. Find a dotted Watchers Eye with Malevolence and other useful accessories. My RF Inquisitor has multipoint with cool Malevolence and Ice Purity physics. This can be very expensive, but it is worth it as it increases your damage and defense compared to the cost of a jewel box.

That's all I can do now. But you have a lot with it! Good luck.