Now, to paint a picture of some of the suggestions you’ve made:
Charm:
Alex goes through a simple process to create this Effect, requiring the collection of some public resources as well as the expenditure of personal resources. The delivery mechanism requires Brook to fall for a trick (drink a ‘spiked’ beverage). Brook, to preempt this, could be wearing the Crown of the Empire or the Headpiece of the Savior, items publicly known to confer immunity to the wearer to Charm effects, but as this immunity is easily visible, Alex can avoid Brook altogether or utilize a counter-Effect to this immunity (somehow get Brook to take it off or lose the right to wear it). Brook might also secretly be the Royal Assassin, a role which requires one to undergo a ceremony to become immune to charm effects too (a preemptive counter that (if applicable) costs XP as its resource and is limited to one unidentified player). Now, Alex has a challenge to get this Charm effect to go off, and for that amount of effort might expect good bang for their buck. They payoff, assuming Alex doesn’t squander the effect on the wearer of the immunity items, is either to get the Charm off or to identify the Royal Assassin - a win win.
Conversely, Alex instantly casts a Charm Effect using a personal resource. Approximately 10% of the player base took preemptive immunity to Charm with unlimited uses (costing a personal resource of XP). The Effect is a stark ‘Charm-Yes’ or ‘Charm-No,’ and each ‘Charm-No’ will put Alex off trying further as it yields zero return, while each ‘Charm-Yes’ will encourage the 90% without the preemptive immunity to invest in it, as the prevalence of Charm makes it return more and more. Overall, the interactions are simple and an arms race ensues until the effect is useless on anyone except new players. In the end, lose-lose.
Pickpocket:
Alex goes through a simple process to create this Effect, attaching pegs to Brook’s clothes - two per item searched, and overcoming Brook’s skill of observation (and that of third parties). Beyond skill at observation, Brook has very little to counter this effect at the time. Regardless of how well Brook hides thing on their person OOC, the presence of the pegs overcomes this. However, Brook can have invested in a post-Effect counter, spending a personal resource of XP, money, and overcoming a roleplaying challenge, to get ‘in’ with the underground. This means that Brook can, after handing over the items, get a clue to the person that stole the items. Further investing in resources and overcoming further roleplaying challenges can get one further ‘in’ with the underground, allowing Brook learn the identity directly, and eventually to have a network of personal thieves capable of returning any items taken off Brook, or pawn show owners that will return Brooks items to them (except Plot items, which will have to be re-stolen by Brook). Now, theft is generally positive (invest skill, get resources), but there is a cost - the predator could become the prey. Those that have been robbed can find counter-thieves of their own to track down the person and/or the items, or do so themselves - giving them a chance for retaliation. As successful thefts happen, more and more people will invest in underground influence, but theft is still a valuable skill - you just might have to start covering your tracks (by either investing in counter-counter-thief influence, or having a ‘fall-guy’).