Yoda is more powerful, easily. If their fight would of continued then yoda would of won, sidious did have an unfair terrain advantage and they are pretty close in blade combat, but power isn't all about blade combat. It taked wisdom, intelligence and much more to be powerful. Yoda is very intelligent wise and powerful with his blades, as he uses his ataru form.
Yoda was obviously afraid- or at least wary- of Sidious; he did not try to fight him again.
And then you'll bring up the whole 'he only had one shot' which is correct. Sidious was not only a powerful Force-user; he was a powerful planner. He made things so that the Jedi would most likely never be able to retaliate, if any had survived.
Sidious is very powerful and wise but not that wise. He was very intelligent though being able to plan everything but sidious was obviously scared to fight yoda at first, (if you remember he tried to escape) but then again he was always scared. But anyways they are close and nearly equal but yoda is wiser and they were in senate pods. It is not all about blade to blade combat, my little green friends. lol
I got to give thumbs-up to Yoda. Yoda was able to counter all of Sids attacks except for the lightning blow at the beginning of the scene. He showed no flaws during the sabre battle and was able to dodge all of the pods, and deflect one back. Sids had gravity to his advantage and was basically dropping the pods. Yoda was able to stop one coming down how fast, and send it spinning up at least 7 levels.