Three names that really hold up to this day in the darker side of things Phony Orphants, Prisoners Of The Sun (P.O.T.S) & Bitmonx, their stuff from around 2006 and before lies somewhere between progressive house, progressive trance and psytrance. No overbearing goa leads, just good arrangement and sprinkle of samples to keep thing interesting.
I will add also that so many of the early iboga releases are everything that was ever right about psytrance