I've been rolling with waraxes for my character who intends to become an assassin starting at around 20th-level (building up skills and roleplaying to that point). And I have to say that I really like the character with two waraxes. She's now 17th-level and has the Backstab perk with Sneak at 54 and Armsman 4/5 and Savage Strike with One-handed at 66. With that, she's able to one-shot kill everything I've encountered so far that she's been able to sneak up on. I'm thinking that with the DB hands that she's simply not going to need daggers to kill anything she comes across other than maybe dragons and maybe a few draugr bosses which are a PITA to sneak up on anyway.
Do you really need the massive dagger multiplier in order to be an effective assassin?
The other thing is that I find that once you sneak attack one target, it tends to aggro everything else in the area and daggers don't really cut it for toe-to-toe combat. I intend to go Hack and Slash 3/3 as well so really wondering if those points in Deadly Aim and Assassin's Blade could be better spent elsewhere (or is it Elswyr?).