The real problem with Cityjet is that 7 months later they still have nothing to do with their SSJs. I know of very few successful airlines that take delivery of brand new planes and just fly them on the odd charter flight for months (+ the short Finnair contract).
I am not convinced SEN is part of a strategy or throwing another dart at the board.
There is clearly still some space in Europe for a low cost operating linking secondary/secondary markets and secondary/tertiary markets (think Volotea). I am not sure Cityjet is that airline.