If you can improve the team without giving up valuable assets, and if you can still focus on the proper development path for your young players, then sure.
That's why they did the Tomasino deal. Who knows what he'll turn out to be, but the move fulfilled two things: 1) It gave the Pens a young potential scoring option with pedigree, 2) It didn't cost much at all.
This team hasn't shown enough to warrant risking a player's development though. They could fire Jarry into the sun tomorrow and promote Blomqvist, but the team in front of him could just as easily implode and turn every game into a shooting gallery throughout the next few months. That won't help his long-term development.