Regen is massive for a shaman at every stage of the game, regardless of what gear you have, until you get Torpor. Period. Even then you're insanely happy to have it because lvl 60 character regen is big.
To answer the question about Halfling illusion -
http://wiki.project1999.com/Innoruuk_Symbol_Quests
When Kunark launches, the Innoruuk symbol quests are put in and Trolls that worship Inny can do them. One of the stages of doing the quests grants you a one (1) charge Halfling illusion item that can be used in any zone of the game. You can easily get a freshly charged illusion item again any time you want for doing a very simple camp.
The usefulness of the illusion varies. You still remain an Innoruuk worshiper which carries a very big faction hit with interactions. For what it's worth, I leveled a Troll Shaman of Inny from levels 12-18 off of the Bandits in Lake Rathe (including the Brigands) and saved every red sash in the bank using 10 slot toolboxes. Because of the small faction hits of killing the bandits, my faction was good enough to go into Qeynos with invis, use the illusion on the Docks side, and turn in every sash for the bronze weapons and level 20.