For the C3 sites, passive tanked drakes work fine but you'll have to warp out quite a bit on some sites if you want to run solo. That being said, anything with at least ~30k shield EHP(as in, 30k EHP IN shield) with 50-60% resists I can keep alive if you were to tag along. That being said.. I don't see myself running C3 sites much longer. It might be possible to have a T1 battlecruiser tag along in C5 sites, I'd have to see how I handle those solo to start.
For the ventures, with the C5 static, you should be able to hoover up c320/c540 in sufficient quantities to not be poor. Especially with 6 ventures. I think each site has something like 200m of gas that you'd pull in pretty quickly. A few of those and you're bankrolled for a PvE fleet. Not sure what your main characters are up to, but unless it is high sec incursions, you should come to w-space =)
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