I think Aleks' natural comparison lies with Menchov.
His skillset is similar to Denis, a true all-rounder with a good mountain + ITT combo and a good sprint / punchy abilites for a GT Contender (Despite Menchov never really cared about winning anything other than GT after signing with Rabobank)
For now, Denis is a level above Vlasov, both in ITT and top-end climbing ability, but Aleks is also a good bike handler and, at the moment, doesn't seem to crumble under pressure, unlike Menchov.
I sadly remember how Denis used to miss splits and shed time on critical downhills under pressure (he would be the official winner of Vuelta '05 if it wasn't for this. I'm pretty sure he would have won TdF '08 as well).
Let's see how he performs on TdF. I don't see him on the podium, but Top 5 is definitely within his reach.