Skills with no change in description of upgrade in preview?

[veevoir]

As per title.. what does upgrading following skills do, anyone knows?

Garrick's Salvaged Rune skill - The preview of higher level of the skill does not show any change in it.. What does the upgrade actually do? Increase chance of getting 'damage' runes? Gets better ones?

Nedir's Summon Servant - nothing changes in upgrade, no indication it will last longer or be stronger... Will it?

[Wlerin]

The Summon Servant upgrade changes the Servant's stats. There's not really a UI component to show this...

Garrik... doesn't really understand how his runes work, so neither do we? It's believed to increase the effects of his damaging runes, and possibly reduce how much the healing one heals.