While PvP is always going to have a bit of RNG, I personally believe the level involved in Improvisation is too much to be acceptable. Please rework it into something like this:
The Perfect Crime
You can use stolen skills twice. Your healing, utility and elite skills are all recharged by 20% each time you steal.
This doesn't change the general philosophy of the game play and what Improvisation is designed to reward too much. You get to use stolen skills twice and you get to use your healing, utility, and elite skills more often the more you steal.
I believe this will make it more even and healthier overall. Yes, you lose the highs of getting back to back Daggerstorms or whatever skill you really wanted to use twice. But you also no longer have to deal with it recharging a skill type you aren't even using at all. If your utilities are on cooldown you're always getting that value and momentum out of stealing.
20% feels like a good number as recharging five utilities by 20% kind of feels like recharging 1 utility by 100%, at least in flavor. Plus without the concern of having skills such as Daggerstorm getting used three times in a row due to getting two recharges on two steals, you could actually potentially outright remove the internal cooldown.
I think it'd be healthier for everyone involved than the wildly varying in usefulness RNG it currently results in today.
The Psychomancer: Mesmer Elite Specialization Suggestion