Well I'm playing a sneaky Argonian mage with a dagger for backup, I pretty much picked Argonian because they look badass, not having to worry about running out of breath underwater and the disease resistance is quite nice too. To be honest I've never actually used the Histskin ability, but I'm sure it would be very useful... every level up I've boosted my magicka and I play on master so I pretty much get one shotted by enemies that I can't one shot so I don't have much use for the health regen boost. Oh yeah Argonians get some sneak and lockpicking bonuses which also benefit my sneaky playstyle. I'm kinda wishing I chose to play as a High Elf because I always seem to run out of magicka too fast.