Hey there. High payout ratios with the pipelines are typical. What you want to be looking at is distributable cash flows, which can be found inside of the quarterly reports. Dividends from both Enbridge and TC Energy are well covered on a DCF basis.
There is a large difference between the two pipes and CNQ. CNQ is an oil producer and will be much more volatile depending on the price of crude oil. Overall, I view the pipes as long term holds, while I view CNQ as a higher potential, short to mid-term hold. You need to have entry/exit strategies to benefit from cyclical options such as CNQ so if you'd like a set and forget, I'd definitely go the pipeline route.
And in terms of pipelines, I think it's about as close to a coinflip as it gets between the two. I prefer TC Energy simply because of a more robust natural gas network, but Enbridge is also building out a nice renewable energy portfolio. I don't think you can go wrong owning either one of them.