Development is far from linear. So using MacKinnon's dreadful sophomore season and his 3rd year when he hurt his wrist 30-35 games in (kid was ~PPG at that point despite the rest of the team pulling a collective iginla for the first two months of the season) is a little misleading. I like Aho a lot, but I can't see him ever dominating the way MacK is now and the player MacK is now is the skater you are missing from being serious cup favorites; not the player MacK was during his sophomore slump or when that wrist/hand injured robbed him of his shot & he got frustrated.
Yep, development isn't linear, but I don't think anyone, even the biggest MacKinnon fans would have expected a 35+G, 100 point season out of him (if he continues on his pace) right now. As I already said though, I do agree that Aho does not have the offensive chops that MacKinnon does, but I still think you are underestimating him a bit.
That aside, I don't disagree with your main point. Canes could really use a premier 1C, no question about it.
I'm not saying getting that guy is easy, but with the lottery & JT's pending UFA, it's not as impossible as it used to be.
I still don't think it's very possible, even with the changes. Pretty much every team that has acquired one in the past 10 years:
2016: Matthews (by Leaf's tanking)
2015: McDavid and "maybe" Eichel (by sucking/tanking)
2014: None?
2013: MacKinnon (by Colorado sucking)
2012: None?
2011: None?
2010: "maybe Seguin" via trade
2009: Tavares (By Islanders sucking)
2008: Stamkos (by Tampa sucking)
2007: None?
2006: Backstrom (by Caps sucking)
2005: Crosby (By Pens sucking the earlier season and the weird lottery due to the lockout)
About the only 2 teams to acquire an elite or near elite center via trade was because the Bruins made a couple bone headed trades (Seguin and Thornton). They are like "gold" so teams that have them very rarely let them get away, until they are no longer elite.
I do think Necas is going to surprise some people though. I haven't seen him that much, but every time I have seen him, I come away saying he's got that "it" factor. He's the only Canes prospect in the last 10+ years I've really felt that way about. I think he'll be much more of a distributor of the puck than a scorer.