I've played/brewed different versions of BR control off and on for awhile, and this pretty close to what I've settled on a couple times. I like the numbers, in your list as well. I always struggled against other control decks in the format, like UB Teachings and MBC (depending on their draw). Similarly, decks like Affinity and Soul Sisters/Tokens could give me headaches if the removal I drew didn't line up right. How did you find those matchups? I'm always torn between Mogg War Marshal and Keldon Marauders in this shell, any thoughts?
Just brainstorming, but I do have a couple ideas for your life gain/ card advantage issues.
-3 Read the Bones
-1 Sign in Blood
+1 Grim Harvest
Reeling the Shock and Draw effects back should make a huge difference in life lost during the match. Faithless Looting is digging, not card advantage, but it's very efficient at what it does. The extra graveyard fodder could even make a 4th Angler playable if you find you need it. Grim Harvest is just a great card for BXx midrange/control decks like this, and is a good Looting pitch. The Keldon Marauders/Grim Harvest loop could be a great finisher for some matchups.
-1 Haunted Fengraf
-1 Evolving Wilds
+1 Rakdos Carnarium
+1 Radiant Fountain
Radiant Fountain adds some life gain to the deck, with Grim Harvest taking over Fengraf's role. I like karoo lands in 2 color decks that are light on lands. Multiples are punishing, so 1 seems fine. Great to see in the first few turns, and plays well with Fountain and the Cycle-Lands in the late game.
-1 Swamp
+1 Bojuka Bog
This swap is just personal preference. So many decks in pauper interact with their graveyard in some way, and I like this as a bit of "free" game 1 hate. Also plays well with karoo lands.
I would try making space for 2-3 Raze somewhere in the sideboard. It's just so punishing against greedy 3 color decks, and anyone playing multiple karoo lands.