As long as we're sharing personal experiences - up to 12 I did CB and
soloed in Butcherblock (goblins, chess pieces). 12 to about 16 I did in
N Ro - great soloing grounds, if you find a group or get in on rotation
you can take Derv camps that give great loot for the level. 16 - 20 I
spent in High Pass. Don't know about other servers - on Solusek Ro HP
was considered a FFA zone - i.e. everyone would try to steal. That's
great for me, as a lone wizard I was able to take blacks and yellows
regularly because groups would always try to steal and help me out in
the process. 20-27 I spent in MM and Lake Rathe. Soloing in MM is hard,
though I did pull it off. Lake Rathe is solo only, if the aviaks are
camped you get in on rotation. 27-30 I spent in Cazic, yes soloing. Most
people will say this is BS - but it is true, I regularly soloed in the
maze and in the TR CY. It is possible to pull singles, you just have to
know what you're doing and know where you are. Now at 30 I see no
soloing alternatives (no I won't camp treants or any good monsters for
that matter) so I'm seriously thinking about quitting.

--
Sergey

Worker bees can leave
Even drones can fly away
The queen is their slave