Even with 20% from Reck, going to 25% gives you an additional 3.33% DPS (1/1.25 - 1/1.2). How much phys mastery + crit can you get from those two relics? Enough to increase your DPS over 3%?
Heck, even with 20% Reck and 20% AM, going from 40 to 45% is worth 2.4% DPS
With my proposed build, a lot of your damage is going through DoT's, which stay on for 32 seconds.
Unless I am mistaken and PM does not add to bleed damage, the crit and % bonuses from melee sets would do well to stack with the 1400 PM you gain from the relics.
Once you have established the dots, you can chuck around impact hits (WoS/DbD) and it's not really an issue maintaining the dots.