Another vote for H/H. The gain from HP is just too miniscule on Absorb and the other 2 abilities doesnt scale at all.
While HS can give a slightly faster buble in some cases, you have to remember its an 8 turn cd ability and not terribly reliable for defense like the much faster dodge.
With HH you gain more health from Sunlight, which also jacks your Blood Drain through the roof. Ive seen some truly massive heals from Sunlighted Blood Drains, 800+, which works superbly with the extra max health gained. Effectively turning you into a health tank.