They needed a lot more time. Beef ribs are loaded with connective tissue, which is delicious when rendered down to gelatin, but horrible and tough if not. Think brisket. They are going to need to cook more like brisket than pork ribs. They need
long low and slow cooking, to break down all that connective tissue and become tender. Depending on the size of the ribs, I could see them taking 6-10 hours. You might consider wrapping in foil halfway through. Also, do a search on this forum for "beef plate ribs". Although plate ribs are probably a slightly different part of the rib than chuck ribs (or short ribs), pretty similar long cook technique. I would not be afraid to wrap the ribs you've already cooked in foil with some liquid, and throw them in a 300 degree oven for a couple hours. They just need more cooking to tenderize.
A longer smoking time should solve all of your problems, with tenderness, bark, and smoke penetration. How much wood did you use? You might have had enough wood for chicken, but beef usually wants more wood/smoke. Many of us like different amounts of smoke. Keep experimenting with the amount of wood until you find what you like. I tend to use a little more wood than what's in the wood chart because I like a little more smoke most of the time. Chicken and beef ribs will never smoke in the same amount of time. 4lb chickens usually only take a couple hours at 250 for me, so you'd want to start your beef ribs at least 4 hours or more before your chickens. And beef ribs can be resting while the chickens are still smoking.
Here's a good post by gregbooras on plate ribs, but there are probably many more.
https://www.smokinitforums.com/index.php?topic=4283.msg38758#msg38758
