Jalonen has his favorites, just like any coach, but IMO while his track record with the issue of trying some fresh blood could be better, it's still actually more pronounced than any of his predecessors'.
Granlund and Vatanen you already mentioned. Then there's also been at least Leo Komarov, Joonas Järvinen, Jani Lajunen and Oskar Osala who Jalonen has brought in as somewhat unproven twentysomethings and given them WHC minutes. The list gets even longer if we're to look at EHT. And while you mention Aaltonen as somebody who could be a drag these days, back then he was hardly the foregone conclusion he might be now, given how he made his major tournament debut at 24 after a very strong showing.
TBH, we haven't seen this many relatively young players break it after Aravirta brought in OJ, Hagman, Niko Kapanen and such in the turn of the millennia, and even those were somewhat proven cases already. Erkka did practically nothing to take any blind chances, he always played it safe. So in that sense, I don't think it's fair to rag against Jalonen for not doing his part in attempts to widen the player pool.
In fact, if you wanna see even more hail mary picks than Jalonen has taken, you'll have to go all the way back to the early 90s when Pentti Matikainen was the coach.