Can be different, but they are still the same type
•too easily measured/compared
•one can too easily become 'just better'
Usually what it offers is a few games to try and see which one is the best, often, quickly becoming a 'need this and that's it', not a choice. Many talents similarily to Cauterize, end up being 'fillers' that just fill the empty spots but aren't ~ever used.
As CC/mobility, Dmg, Defensive row
The talents are very different types
•allows a spell with less 'value' to still be a better choice, based on playstyle/situation
•bigger decision to make, can go with the completely wrong/right choice
•difficult to compare, ~completely different types
•bigger impact on gameplay, more customization to playstyle
•vast combinations for specializations in a 3v3 team
•potentially difficult to determine a 'best choice', every choice has advantage/disadvantage, strength/weakness
It lets Cauterize and Greater Invis to be worse than Cold Snap, but still be sometimes chosen. Easier to make 'fun', unique, but useful talents.