What is your melee diviner main stat, str or int? Is it physical or vitality damage based? In case it is int/vitality you are really missing on distort reality, and temporal rift too. Combined with necrosis it is a killer skill even if on relatively long cooldown with no -recharge items.
And as a melee diviner you don't really care of the liche dps: with phantom strike or ternion your dps will be far above the Liche.
it's nice that you included arcane blast in the list.. in IT, it was considered a poor skill investment.. but since AE, the liche now spams it.. on my bonecharmer, i chose it over death nova.. but that was because i have flush out.. ToW also has reduced resist but it's % while flush out is absolute.. it's true that death nova deals better damage but the liche doesn't spam it.. i felt arcane blast was a better investment for my bonecharmer.. diviner is different and i have no experience for a diviner so i would abstain from voting.. however i would suggest that you spread out your skill distribution even more.. i would even take off some points from liche king and put 1pt each on its upgrades or until the 3rd upgrade (not sure).. i also like 1pt on that mind control skill
however, I'm thinking something different.. a melee diviner has the potential to deal loads of vit damage.. so if it was me, i would make it a hybrid.. having enough int would make it easier to get good CDR.. high enough CDR could mean permanent dark covenant/unearthly power, more frequent casting of dream CC, phantom strike, and outsider.. ToC to alleviate some of the HP regen penalty from dark covenant