As a result of these changes you need a 95 in order to pickpocket Drizzt's swords and a 50 to pickpocket Algeron's cloak (I've tested both and they do work).
As for Phlydia's amulet the best thing to do in her case would be to move it into her inventory. That way you only need 10. It is after all effectively BG1's training area (it never had a tutorial).
Anyways since its a new feature I figured I'd create a thread for it to report any bugs being experienced. From my experience it seems to only let you pickpocket weapons if they aren't weapons that a neutral (non-hostile) character has equipped. I'm assuming that is intentional and not a bug and that its that way namely to prevent you from successfully pickpocketing something like the "weapon" Drizzt actually uses to attack with (its not an actual weapon).
I guess if you find any inconsistencies/ bugs with the new system write them down here.