Am I just having a bad luck streak with finding resource nodes? I'm on Tatooine at level 27 and have uncovered most of the map, but I'm finding very few Arch nodes. Comparatively, there were plenty on Dromund Kaas and even Nar Shadaa (which makes me scratch my head given the nature of that planet).

I know I can send companions off to mission resources, but that is starting to get rather expensive at Tier 3 & 4.