Here's a tiny comparison of players who played in KalPa on their d+1 season:
Artturi Lehkonen (2013-14): 33gp 7+13=20 (his d-1 season: 45gp 14+16=30)
Kasperi Kapanen (2014-15): 41gp 11+10=21 (his d-1 season: 47gp 7+7=14)
Joni Ikonen (2017-18): 52gp 4+10=14
Ikonen played in Sweden during his d-1 season, mainly in the juniors, 10 games and 0 points in SEL.
Lehkonen was the 2nd best scorer for KalPa in 2012-13 and the best in 2013-14 (yes, the team sucked and he was the top scorer with 20 points in a 60 game regular season).
Kapanen was 7th in scoring in 2013-14 and 6th in 2014-15.
Ikonen was 13th (2017-18).
At points during last season Ikonen was actually healthy scratched IIRC, although only for individual games, not so that he would have been sent to the juniors. At times he played very well, other times not. Considering his past performance in comparison to others (not only to Lehkonen and Kapanen) and his injury I have to agree with
@HOPE, there's very little chance he'll become an NHL player. Hopefully he can stay healthy and gets his development back on track - even if he does, my expectation for him is a decent FEL career, nothing more.
I (among the majority of Finns) have considered Joni to be less talented than his brother Juuso. Strangely Joni was drafted on the second round whereas Juuso was never drafted. It might be because Juuso is way too small for an NHL player - 2cm shorter than his little brother
I guess as a draftee Joni was seen to have more small rink capabilities than Juuso. Juuso's production in juniors and in FEL were considerably better when he was Joni's age.