I would not try and smoke a Tri-Tip like a brisket - way too lean a cut of beef and you'll have an awful mess of dry meat on your hands. Tri-Tip is best cooked like a steak. Try reverse searing it like thus, and you'll still get plenty of smoke flavor with this method:
For the beef ribs, it sounds like you may have gotten what I call slim pickins dino bones. I see these periodically at the market. Just smoke them till the meat is just about to fall off the bones, but not quite.
In the future, when it comes to beef ribs, try and get beef back ribs. They're quite a bit smaller, but exponentially meatier.
Let us know how everything turns out!