New to sous vide and not having any luck
Sous vide is a great method for getting tender meat but it doesn't impart flavor to anything. Marinades only go so far adding flavor, you need your meat to have flavor in the first place. Other than from marinade flavor in cooked meat comes from:


The quality of the meat: good quality meat comes from good breeds that have been raised well and given quality feed
The cut: the more work the meat does on the animal the more flavor it has. A tenderloin is tender to begin with because it just fills a gap and doesn't move, but it isn't going to taste the same a shoulder. A working cut has a much stronger flavor and the connective tissues break down into gelatin which adds flavor and a luscious mouth feel. My personal opinion is that there's no point in slow cooking tender cuts, I always go for the beef shin (leg), chuck, or rump (round). Chicken breast, especially your standard cheap store brands, has very little flavor, I prefer dark meat, or if I'm cooking breast I go for quality free range birds
Maillard reactions and caramelization: When cooking at high temperatures you get flavors from maillard reactions and the caramelization of sugars, slow cooking does not add these, so you need to brown before or after (you appear to have done this with your beef which is good), before is better for slow cooking in my opinion as you get the flavors from the browning throughout the meat


The simple truth is you won't get a tasty result in cooking unless you start with good ingredients, and this is especially true in sous vide cooking, or any slow cooking method really. Sous vide is not a magic bullet which transforms mediocre steak into amazing steak, it's got to be amazing steak in the first place. Good restaurants use the best quality meats they can get their hands on, so if you want to get similar results you will too.