When it comes to Economic Victories, its more to do with how much Dust you're able to produce. So if you're looking for an Economic Victory, here are some tips.

1) Population Buff. Any faction that produces Dust(*cough* Lumeris *cough*) will have a considerable impact on your chances of an Economic Victory. Cravers and their Extreme Foremen buff are also not to be discounted because they exploit planets at 2.5 times their base yield(which in a custom Gene Hunter faction is straight up broken). Granted Cravers buff will not last since inevitably planets will be exhausted and their output will drop from 2.5 times base yield to their yield being cut in half. Oh and don't forget Riftborn. Their Adept Workers buff is insanely OP if you're able to mass produce their population.

2) Planets you occupy. Sterile planets generally produce the most Dust(ex: Toxic and Desert primarily) but Temperate and even Fertile worlds generate a modest amount of base Dust. The bigger the planet, the more population that can be stationed there and hence total output you can obtain(this is where Crowded Planets faction trait has an impact). Riftborn are generally solid in this area because they specialize in colonizing Sterile planets thanks to their Gameplay Affinity and their Biophobic trait.

3) Develop Economy&Trade tree for Dust System improvements. The faster you unlock Dust improvements, the faster you'll have your population cranking out Dust.

4) Enact Dust Laws. Supreme Tax Act is a good early game example of generating gobs of Dust for a flat penalty but there are other Independent and Ideological laws(Pacifist in particular) that can buff Dust output significantly.

5) Keep your citizens happy!! If your citizens become happy or better yet escatic, you get a buff not only to Empire Science output but also to Dust production. Also affects Food and Influence production but on a system by system basis.