Personally, I'm 100% sold on Kakko being THE #2 guy.
One of the key reasons Kotkaniemi was so attractive is that he performed well against men in the Finnish Elite League (SM-liiga, "Liiga" for short), the top Finnish pro league. Another key reason: he stood out at the WJC.
10 goals and 29 points through 57 Liiga games (2017-18)
3 goals and 9 points through 7 WJC games (2018)
Remember all the HYPE! surrounding Patrick Laine? Same deal:
17 goals and 33 points through 46 Liiga games (2015-16)
7 goals and 13 points through 7 WJC games (2016)
13 goals and 28 points through 50 Liiga games (2015-16)
5 goals and 17 points through 7 WJC games (2016)
9 goals and 28 points through 56 Liiga games (2014-15)
2 goals and 5 points through 7 WJC games (2015)
21 goals and 48 points through 53 Liiga games (2012-13)
3 goals and 7 points through 6 WJC games (2013)
13 goals and 40 points through 43 Liiga games (2009-10)
1 goal and 7 points through 6 WJC games (2010)
So that gives us some perspective. If you're surpassing or even merely flirting with 30 points in the Liiga as a 17-18 year old and your name isn't Jesse Puljujarvi, your floor is probably high and your ceiling is wayyy up there. (Barkov is arguably the best two-way pivot in the NHL. Laine, Rantanen, and Granlund are big-time scorers.)
That being said, here are Kakko's numbers:
11 goals and 22 points through 29 Liiga games (2018-19)
2 goals and 5 points through 7 WJC games (2019)
My thoughts on Kakko, beyond just the production? I think he's pretty close to perfect. He's elite in nearly every meaningful category and he doesn't have any meaningful shortcomings. He's the Platonic ideal of the modern-day power-forward made flesh. The total package. If Jack Hughes is playing chess while everyone else is playing checkers, Kakko is crushing everyone at checkers.
Is he better than Kotkaniemi was at this time last year? I think so, yes. Kotkaniemi is maybe more valuable because he's a centerman's center (Kakko's a natural winger who plays center sometimes). Beyond that, I think Kakko has him beat in pretty much every way. The biggest thing is the skating; Kakko is an outstanding skater, which gives him a dimension that Kotkaniemi lacks. If Kotkaniemi skated like Kakko, Kotkaniemi might've been drafted 2nd overall.
I'd say Kakko is more similar to Svechnikov; they're both ultra-projectable all-around scoring wingers. I think Kakko is a little more tantalizing than Svechnikov was at this time last year, as Kakko is excelling in a tough pro league (Svechnikov was dominating the OHL) and Kakko arguably delivered the more impressive WJC performance (Svechnikov registered no goals and 5 assists through 5 games at the 2018 tournament).
tl;dr Kaapo Kakko is the real deal.
I'll follow this up with some thoughts on Podkolzin and Cozens. Have to head out for a bit.