I always liked Crystal Caverns but may not find a log
Of groups. Do spiders, terrors and Geos at bottom. But again may not
Have groups.

Geodes in CC will almost always be camped by someone, and sometimes there's even a small line. But whether or not people want to share the camp and group with you is another matter. Geodes can be a big cash spot after all if you have even average luck with named spawns.

Get a mage partner and go to droga. xp will fly.