As stated above, it all depends on how you play and what type of build your char has as well as what you can handle. For example, mine is mainly melee with some magic and well...I suck with multi aggro enemies(currently training windmill, it helps a lot in bad situations). So for me, the order would be: Alby(duh lol), Rabbie, Runda, Fiodh(only reason it is behind Rundal is because of those bloody Gorgons >.>), Ciar, Math, and Barri (The only reason Coil, Peaca, and Ceo Island are not listed is because I havent tried those yet, but I heard that Coil and Peaca are cool for mass raids
). Also, the reason that Math and Barri are last is becase of a)they multi aggro a lot(and barri has imps
) and b) cant fight the golem that efectively/its annoying fighting the ogre warriors due to their immense hp. Well, I hope this helps you ^_^
Edit: Oh, and before I forget, I arranged them in what I think their difficulties are to solo. If in a decent party(4-5 tops), Ciar and Barri are after Alby...but trust me..the funnest time I had in a dungeon when a party of guildies and I raided Rabbie...epic windmill by a Metal Skeleton nearly knocked us all out and we saw the mini skeletons ^_^