As it happens, I travelled Helsinki–Torino this way:
Evening of Wednesday last week: Leave Helsinki 16:35, TallinkSilja ship from Turku 20:15, reach Stockholm 06:10.
Thursday: Leave Stockholm 07:24, reach Hamburg 19:00, night train to Basel 21:52 (from Hamburg-Altona).
Friday: Arrive in Basel 08:10, continue to Lugano 09:03, change there and in Milano, reach Torino 15:10.
(I actually intentionally took a slower "scenic" route from Bellinzona to Torino,)