I have some mild concerns because both Game of Thrones 1.0 (Damon) and Star Wars LCG (Erik) are hot messes. Make of that what you will. Damon also brought us some really messy Caïssa and Call of Cthulhu cards.
But the whole design team has done a fantastic job so far building up the Netrunner structure. Lukas may have been lead designer, but it took a lot more people than just him to bring us the game we know and love today. Both Damon and Erik already have at least one cycle’s worth of experience working on Netrunner, so I’m confident that they will handle the transition well.
From a card pool perspective, they have a great baseline to work from. Fresh eyes always means new ideas, which are good for the health of the game. Looking at other card games, the first cycle under new management might be a little bumpy, but I can’t possibly inagine how that could “kill” the game. People like to play Netrunner.
From a design process perspective, Netrunner has a lot of great systems in place. Cards are tested thoroughly in house (which I’m sure Lukas will be a part of). Cards are tested all over the world by playtest groups. Cards are edited and revised both in house and out of house. As long as none of those systems fall out of use, then it seems like Netrunner has a lot of life in it yet. The only scaffolding I’m worried about losing is getting rules questions answered.
Tl;dr I’m a little worried, but I think Mumbad cycle shows that Erik and Damon have learned a lot, and I respect their work. I am confident that they will do a good job, especially if they keep making use of everything that makes Netrunner what it is (including the awesome community).