Worked in getting an NHL contract. After all, that's obviously why European players come to North American junior leagues to play. To earn more ice time and to get interest from NHL clubs.
Tolchinsky was able to play well enough in the OHL to earn an NHL contract (proving to NHL scouts that he's worth a shot despite his size). I think it's pretty obvious that, that's Tkachev's goal too.
He wasn't drafted. That in itself isn't success.
We will see how he pans out. Being drafted by an NHL team, or being signed by one, isn't success. The NHL isn't the be all and end all as a career, but if we're using it as the defining principle, then at least quantify a sizeable NHL sample size with some results as success .... not an affliation that cannot possibly be assessed yet.
Will be interesting to see how Tkachev performs. Everytime i've seen him, i've been impressed. Still, given size, lack of a truely well rounded game and his nationality, he'll be drafted much lower than natural ability and entertainment would suggest.