Using your guide and adjusting it my playstyle - without stealth or mark of death upgrades (both which I don't use much) I got this:
Repec at level 5 (which I usually am when I can get to Maker's Sigh, after opening chest at home):
1. Backstab
2. Unforgiving Chain
3. Explosive Strike
4. Speed
5. Blindside
6. Precision, Power (Tome)
7. (Assassin), Mark of Death
8. Merciless Strike, Twin Fangs (Tome)
9. Bloodlust
10.Reversed Grip
11.Pinpoint Strikes
12.Assassinate
13.Devious Harm
14.(Duelist) Annihilate
15.Throw the Gauntlet, Parry (Tome)
16.Vendetta
17.Sure Stikes
18.Blood Feud
19.Overkill
20.Harmony
21.Lightning Speed
22.Energizing Speed
23.Evasive Maneuvers
The level 6 skills may not be helpful right then, but it got me to unlock lightning and energizing speed sooner - which was the goal.
Would this adjusted set-up be alright on Hard?
Also, Merril, if I replaced her with Varric or Isabella, would that weaken your set-up too much? If not, and if its not too much trouble, could you give a suggestion on their build? The one reason I had this thought is because with Isabella on my team, chameleon breath and such helped out. I like the Anders and Aveline set ups very much.
Thank you very much for this guide, it was helpful.