If you stay on lvl 35, here's some quick maths regarding your Chaos Crystals problem:
1 x Jealousy Crystal is 9.5-10k
1 x Green Bonus Changer is 4.6, but can be sold for more.
From my experience, you usually drop at least 2-3 Changers, with changers of dropping as much as 5, not to mention the occasional Researcher's Elixir and Ingenuity. 2 Green Changers alone give you as much profit as if you'd sell 1 Chaos - you also get to drop lots of 30 weapons +7, that's how I found my 42 AVG Bell, so better break them.
Hope this helps.
If you're patient, Alchemy can be very profitable as well.
3.6k per Cor, 25 Cors equal 90k per day if you don't break them.
Breaking them requires a bit more knowledge about the value of each individual alchemical piece. I personally wouldn't advise going into Refining and Upgrading Alchemy until you really understand it.