I ran a long running campaign which included liberal use of both Stim Application and its improved version.
I didn’t really mind the power increase, but I felt it was appropriate to add drawbacks overtime with its constant use. They started off relatively small; I’d flip a destiny point to reduce the character’s strain threshold for the remainder of the encounter. Sometimes, after consecutive encounters of use, I’d require resilience checks to avoid withdrawal symptoms and/or gaining the addicted obligation.
I tried to avoid being heavy-handed with the drawbacks, and my group seemed to enjoy the added consequences. However, every group is different, and some players may feel unfairly treated when dealing with drawbacks to their favorite ability.