I think it will make a difference for classes that have abilities that work with max HP. (I think the Skar will make great DL's especially since DL can increase things like regen and manipulate their HP so much) i.e. It is very likely that the DL will have some abilities that manipulate their max HP, and the cleric has abilities that allow them to match their HP pool with their defensive target and then heal a target for that amount, while it is also likely that they will be able to further increase a character's max HP. Dwarves can't be DL's and stats at end game will likely all a hard cap that can be met through gear/buffs. If the DL is capable of raising their max HP by X%, this would make the Skar passive compound this effect, making that ability stronger on a Skar... and I am really thinking that the DL will be able to do something like this at some point.
I was really attracted to Skar until I got a look at their passives, extremely underwhelming besides the fear resist.
2% speed per skar would go a ways instead of 1%. Outside of starting areas how often are you going to have ALL skar group members to take advantage of the speed buff anyway?
And not only is the 5% health increase a bit boring, it's really lackluster - I would prefer health regen. The issue is the 5% doesn't matter until you're down to your last 5% in a way? Health regen would have lasting effects in fight, out of fights. That would be extremely useful and not OP.
Raidil said: I really want to play a skar I just don't want to be hamstrung
Joppa commented on this in a stream not long after Passives were revealed. He tried to make it clear that Racial passives are about 'flavor' and shouldn't keep anyone from choosing the Race they like the most for their class. Because "all Races can do well in any Class that is open to them".
So if you can't find a definitive reason to pick one Race or the other, then you don't have to worry. Pick the one you like the most.